Worksite proximity warning

ABSTRACT

Systems and methods for warning of proximity in a worksite are disclosed. A second transceiver is detected at a first transceiver, wherein the first transceiver is a mobile wearable device, and wherein the first transceiver and the second transceiver are located at a worksite. An ad-hoc network is established, at the first transceiver, between the first transceiver and the second transceiver. A distance is calculated, at the first transceiver, in three dimensions between the first transceiver and the second transceiver based on the detecting the second transceiver. A first safety envelope is defined, at the first transceiver, about the first transceiver and a second safety envelope about the second transceiver. An alarm is issued, at the first transceiver, when the first safety envelope comes in contact with the second safety envelope.

CROSS-REFERENCE TO RELATED U.S. APPLICATIONS

This application claims the benefit of and claims priority to U.S.Provisional Patent Application No. 61/940,884, Attorney Docket NumberTRMB-15001.PRO, entitled “METHOD AND TRANSCEIVER FOR PREVENTINGACCIDENTAL COLLISIONS,” with filing date of Feb. 18, 2014 and isincorporated by reference in its entirety.

This application is also a continuation-in-part application of andclaims the benefit of the co-pending U.S. patent application Ser. No.14/171,489, Attorney Docket Number TRMB-2918.CIP1.CON1, entitled “SENSORUNIT SYSTEM,” with filing date Feb. 3, 2014.

U.S. patent application Ser. No. 14/171,489 is a continuationapplication of and claims the benefit of the then co-pending U.S. patentapplication Ser. No. 13/708,843, Attorney Docket Number TRMB-2918.CIP1,entitled “SENSOR UNIT SYSTEM,” with filing date Dec. 7, 2012, by GregoryC. Best et al.; U.S. patent application Ser. No. 13/708,843 is assignedto the assignee of the present application and was incorporated byreference in its entirety into U.S. patent application Ser. No.14/171,489.

U.S. patent application Ser. No. 13/708,843 is a continuation-in-partapplication of and claims the benefit of then co-pending U.S. patentapplication Ser. No. 13/017,320, Attorney Docket Number TRMB-2918,entitled “SENSOR UNIT SYSTEM,” with filing date Jan. 31, 2011; U.S.patent application Ser. No. 13/017,320 is assigned to the assignee ofthe present application and was incorporated by reference in itsentirety into U.S. patent application Ser. No. 13/708,843.

The application with U.S. application Ser. No. 13/017,320 claims thebenefit of and claims priority to U.S. Provisional Patent ApplicationNo. 61/300,360, Attorney Docket Number TRMB-2729.PRO, entitled “LIFTDEVICE EFFICIENT LOAD DELIVERY, LOAD MONITORING, COLLISION AVOIDANCE,AND LOAD HAZARD AVOIDANCE,” with filing date Feb. 1, 2010.

BACKGROUND

When using a lifting device, such as for example, a crane, it is oftenvery difficult or impossible for an operator to see the area around andbelow the load that is being lifted, moved, or positioned by the liftingdevice. As but one example, some lifts are blind to an operator of thelifting device, such as when a load is dropped into a hole. As such, itis difficult and sometimes dangerous to perform lift activities. This isbecause the lifting device operator cannot see the position of the load,and the hazards that might hit or be hit by the load. Even routinelifts, where a lifting device operator can view the load, can becomplicated by diminished situational awareness regarding the positionof the load and/or potential hazards in the vicinity of the load.

Additionally, a worksite, a job site, or work area often has more thanone lifting device in operation at any given time. As lifting devicesare often in movement and require immense concentration to operate, itcan be difficult for an operator to constantly determine if there isadequate clearance to prevent collision of some portion of his liftingdevice or load with a portion of another lifting device or anotherlifting device's load.

Furthermore, having real time knowledge of the absolute position andorientation of the load, in coordination with a mapped or modeled jobsite, can facilitate and increase the efficiency of delivering this loadto the coordinates of the desired destination.

Construction sites are populated with a broad range of equipment andobstacles. Many hazards exist. For example, because of noise ordistractions, personnel walking on foot on a construction site might nothear a vehicle coming from behind, or might not notice the closeproximity of a moving crane hook block.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and form a part ofthis application, illustrate embodiments of the subject matter, andtogether with the description of embodiments, serve to explain theprinciples of the embodiments of the subject matter. Unless noted, thedrawings referred to in this brief description of drawings should beunderstood as not being drawn to scale.

FIG. 1A is a diagram of an example lifting device sensor system in placeon a lifting device, in accordance with an embodiment.

FIG. 1B shows an alternative coupling of a sensor unit of the sensorsystem with a lifting device load line, in accordance with anembodiment.

FIG. 2A is a diagram of a selection of sensor unit components coupledwith a housing of a sensor unit, in accordance with an embodiment.

FIG. 2B illustrates a selection of features of a lifting device sensorunit, in accordance with various embodiments

FIG. 2C illustrates an example load line positioner coupled with ahousing of a sensor unit, in accordance with an embodiment.

FIG. 2D illustrates an example sensor unit coupled with a hook block, inaccordance with various embodiments.

FIG. 3 is a block diagram of additional lifting device sensor unitcomponents that may variously be included in a lifting device sensorunit, according to one or more embodiments.

FIG. 4 illustrates a display of an example lift plan that has beengenerated by a lifting device sensor unit, according to an embodiment.

FIG. 5 illustrates a display of example lifting device geofenceinformation that has been generated by one or more lifting device sensorunits, according to an embodiment.

FIG. 6 is a flow diagram of an example method of monitoring a liftingdevice load, in accordance with an embodiment.

FIG. 7 is a flow diagram of an example method of lifting devicecollision, in accordance with an embodiment.

FIG. 8 is a flow diagram of an example method of lifting device loadhazard avoidance, in accordance with an embodiment.

FIG. 9 shows an example GNSS receiver that may be used in accordancewith some embodiments.

FIG. 10 illustrates a block diagram of an example computer system withwhich or upon which various embodiments may be implemented.

FIG. 11 is a block diagram of an example ad-hoc wireless personal areanetwork in accordance with one or more embodiments.

FIG. 12 is a block diagram of an example ad-hoc wireless personal areanetwork in accordance with one or more embodiments.

FIG. 13 is a block diagram of an example communication network inaccordance with one or more embodiments.

FIG. 14 is a flowchart of a method for communicatively coupling a sensorunit system in accordance with one or more embodiments.

FIG. 15A is a diagram of example lifting device sensor unit componentscoupled with a housing of a sensor unit, in accordance with variousembodiments.

FIG. 15B is a diagram of example sensor unit components, in accordancewith various embodiments.

FIG. 15C is a diagram of an example sensor unit system in place on amobile construction device, in accordance with an embodiment.

FIG. 16 is a diagram of a site utilizing components for determining thelocation of a lifting device sensor unit in accordance with anembodiment.

FIG. 17 is block diagram showing components of an example positiondetermining component in accordance with an embodiment.

FIG. 18 is a block diagram of an example communication network inaccordance with one or more embodiments.

FIG. 19 is a block diagram of an example communication network inaccordance with one or more embodiments.

FIG. 20 is a flowchart of a method for providing sensor unit locationdata in accordance with one embodiment.

FIG. 21 is a flowchart of a method for providing sensor unit locationdata in accordance with one embodiment.

FIG. 22 is a block diagram of an example environment for warning ofproximity in a worksite in accordance with one or more embodiments.

FIG. 23 is a block diagram of an example transceiver for warning ofproximity in a worksite in accordance with one or more embodiments.

FIG. 24 is a block diagram of an example transceiver for warning ofproximity in a worksite in accordance with one or more embodiments.

FIG. 25 is a block diagram of an person with objects for warning ofproximity in a worksite in accordance with one or more embodiments.

FIG. 26 is a flowchart of a method for warning of proximity in aworksite in accordance with one embodiment.

FIG. 27 is a flowchart of a method for warning of proximity in aworksite in accordance with one embodiment.

DESCRIPTION OF EMBODIMENTS

Reference will now be made in detail to various embodiments, examples ofwhich are illustrated in the accompanying drawings. While the subjectmatter will be described in conjunction with these embodiments, it willbe understood that they are not intended to limit the subject matter tothese embodiments. On the contrary, the subject matter described hereinis intended to cover alternatives, modifications and equivalents, whichmay be included within the spirit and scope as defined by the appendedclaims. In some embodiments, all or portions of the electronic computingdevices, units, and components described herein are implemented inhardware, a combination of hardware and firmware, a combination ofhardware and computer-executable instructions, or the like. Furthermore,in the following description, numerous specific details are set forth inorder to provide a thorough understanding of the subject matter.However, some embodiments may be practiced without these specificdetails. In other instances, well-known methods, procedures, objects,and circuits have not been described in detail as not to unnecessarilyobscure aspects of the subject matter.

NOTATION AND NOMENCLATURE

Unless specifically stated otherwise as apparent from the followingdiscussions, it is appreciated that throughout the present Descriptionof Embodiments, discussions utilizing terms such as “determining,”“monitoring,” “providing,” “initiating,” “generating,” “wirelesslycommunicating,” “wirelessly acquiring,” “wirelessly providing,”“accessing,” “communicating,” “using,” “coupling,” “communicativelycoupling,” “detecting,” “establishing,” “calculating,” “defining,”“issuing,” “sending,” or the like, often (but not always) refer to theactions and processes of a computer system or similar electroniccomputing device such as, but not limited to, a display unit and/or alifting device sensor unit or component thereof. The electroniccomputing device manipulates and transforms data represented as physical(electronic) quantities within the electronic computing device'sprocessors, registers, and/or memories into other data similarlyrepresented as physical quantities within the electronic computingdevice's memories, registers and/or other such information storage,processing, transmission, or/or display components of the electroniccomputing device or other electronic computing device(s).

The term “lifting device” is used often herein. By “lifting device” whatis meant is a device that utilizes a load line to lift a load. Somenon-limiting examples of lifting devices include a jib crane, gantrycrane, derrick crane, boom crane (telescoping or fixed), wheel mountedcrane, truck mounted crane, crawler mounted crane, overhead crane,monorail carrier, straddle crane, tower crane, crane with a hoist but noboom, and a hoist. Typically a lifting device lifts a load with a hookor some attachment point located at a distal end/position of the loadline with respect to a lifting point or arm to which it is attached. Aload line is typically a cable, but in some a load line may comprisechain, rope, more than one cable, multiple sections of a single ormultiple cables, or some combination thereof.

Overview

Example units, systems, and methods for lifting device efficient loaddelivery, load monitoring, collision avoidance, and load hazardavoidance are described herein. Discussion begins with description oflifting device sensor unit and system shown coupled with two examplelifting devices. Discussion continues with description of variouscomponents of an example sensor unit that may be used for one or moreof: assisting in efficient load delivery, load monitoring, collisionavoidance, and load hazard avoidance. Techniques of objectidentification in the vicinity of the load are described. Exampledisplays of a lift plan and lifting device geofences are then discussed.Example methods of operation are discussed. Discussion then turns todescription of an example global navigation satellite system (GNSS)receiver which may be used in various portions of the sensor unit andsensor system. An example computer system is then described, with whichor upon which various components, method procedures, or portions thereofmay be implemented. Implementations of an ad-hoc wireless personal areanetwork are then discussed. Discussion continues with a description ofanother lifting device sensor unit in accordance with variousembodiment. In accordance with one or more embodiments, real-timelocation system (RTLS) tag(s) and transceiver(s) are used to determinethe position of the lifting device sensor unit. In one embodiment, anRTLS transceiver is configured to determine the distance to one or moreRTLS tags based upon the round trip time of flight of a signal generatedby the RTLS transceiver and a respective reply from one or more RTLStags. In another embodiment, a position determining component determinesthe distance to one or more RTLS tags based upon the respective signalstrength of a reply from each of the RTLS tags communicating with a RTLStransceiver. In another embodiment, A position determining componentperforms a trilateration operation based upon the distance from thelifting device sensor unit and the known position of either the RTLStransceiver, or the RTLS tags. In one embodiment, the RTLS tags aredisposed at known locations at a site at which the lifting device sensorunit is located and the RTLS transceiver is coupled with the liftingdevice sensor unit itself. In another embodiment, one or more RTLStransceiver are disposed at known locations at a site at which thelifting device sensor unit is located and the RTLS tag is coupled withthe lifting device sensor unit itself. Finally, an example communicationnetwork is described.

Among the main reasons for collision incidents include: machine blindspots, operator fatigue, distraction, repetitive operations, etc. On aworksite, inventory of material and equipment are broadly spread. Someworksites could have a thousand pieces of equipment and even moreinventoried components. Identifying and locating each of them is achallenge. Several known techniques are used to detect proximity.Several of them use global navigation satellite system (GNSS) positionand share the position of different assets on a work site. GNSSpenetration is poor inside buildings, under bridges, or when theconstellation of satellites is not sufficient with the presence ofsurrounding structures. Some non-GNSS techniques use of transmitters onobstacles and receivers on moving vehicles.

Despite recent advances, there remains a need for improved techniquesfor reducing worksite hazards. Various aspects of the present disclosuregenerally address one or more of the problems of reducing safety hazardson worksites. The present disclosure describes using transceivers tocreate ad-hoc networks calculating distances between two giventransceivers. Communication capabilities of the transceivers are used tocalculate distances to provide proximity warnings on worksites. Distanceinformation is shared between the transceivers to warn personnel ofproximity conditions in construction sites, industrial sites, factories,warehouses, and the like. The present disclosure further describesallowing workers to remotely scan an area of a work site to extract theinventory along with the location of this inventory.

Example Lifting Device Sensor System

FIG. 1A is a diagram of an example lifting device sensor system 100 inplace on a lifting device 120, in accordance with an embodiment. Liftingdevice sensor system 100 can be used to assist in or accomplish one ormore of efficient load delivery, load monitoring, collision avoidance,and load hazard avoidance. It is appreciated that two or more of thesefunctions may often overlap. In one embodiment, lifting device sensorsystem 100 comprises sensor unit 110 and one or more display units 113.Dashed lines 115 and 115B indicate wireless communication that occurs orcan occur between sensor unit 110 and display unit(s) 113. Display unit113 may be a dedicated display with a wireless transceiver or may bepart of an electronic device such as smart phone, netbook, notebookcomputer, tablet computer, or the like. It is appreciated that sensorunit 110 is referred to herein in the generic sense as “sensor unit” or“lifting device sensor unit,” and more particularly as “lifting devicecollision avoidance sensor unit,” or “lifting device load hazardavoidance sensor unit.” In some embodiments lifting device sensor system100 further comprises: one or more global navigation satellite receivers(e.g., 108, 107) which are or may be coupled to portions of a liftingarm or a body of a lifting device, such as lifting device 120; and/orone or more object identifiers 102 that may be coupled to objects in aworking area of lifting device 120. As will be discussed in greaterdetail below, in one embodiment, inertial sensors (e.g., 214 of FIG. 2A)of sensor unit 110 can be used to augment, or work in conjunction with,the GNSS receivers 107 and 108 and/or sensor unit 110 to provide liftingdevice sensor system 100 with positioning data. For example, duringperiods when the view to GNSS satellites may be temporarily obstructed,the inertial sensors can provide positioning data which permits liftingdevice sensor system 100 to continue determining the position of sensorunit 110 and/or portions of lifting device 120. As will be furtherdescribed herein, in various embodiments sensor unit 110 is removablycouplable with load line 112, other load lines of similar or differentcross-sectional dimensions, and other load lines of similar or differentconfigurations.

In FIG. 1A, GNSS receiver 108 is coupled to counterweights on the body(i.e., not on the lifting arm) of lifting device 120 and determines aposition of point 143 in two or three dimensions. GNSS receiver 107 iscoupled near the distal tip region of lifting arm 119 (a boom in thiscase) and determines a position of point 153 in two or three dimensions.It is appreciated that one or more of GNSS receivers 107 and 108 maywired or wirelessly communicate their determined positions (e.g., thepositions of points 153 and 143) to operator cab 121 or to a componentin operator cab 121 such as cab mounted display 113A. One suchcommunication is illustrated by 109. Such positions may also bewirelessly communicated to components of sensor system 100, such ashand-holdable display unit 113B and/or sensor unit 110. Likewise, loadinformation determined load cell 122 and/or lifting arm angleinformation determined by angle sensor/inclinometer 116 may becommunicated to one or more components of sensor system 100 in the sameor similar manner.

In FIG. 1A, object identifiers 102A and 102B are coupled to load 104 andidentify information about load 104. Among other things, the informationprovided by load mounted objected identifiers may include informationsuch as: what load 104 is (e.g., an I-beam); the orientation of load 104(e.g., where the sides/ends are and/or which side/end belongs where at afinal destination); and/or the lift destination for load 104. Objectidentifier 102C is located on the cap of person 117A and objectidentifier 102D is located on the helmet of person 117B. In variousembodiments object identifiers may comprise mechanisms such as: RadioFrequency Identifiers (RFIDs); reflectors; bar codes; or some mix orcombination thereof. Object identifiers facilitate identification,location, and/or tracking of one or more objects in the vicinity of aload in the viewing region beneath sensor unit 110. It is noted that inone embodiment, due to the nature of the components (e.g., positioningand communications technology) typically found on modern “smart”cellular telephones and Personal Digital Assistants (PDAs), thecapability of providing an object identifier (e.g., object identifier102C and 102D of FIG. 1A) can be provided using a cellular telephone,PDA, or similarly configured portable electronic having a suitablesoftware application loaded onto it which enables it to be a part of, orcommunicatively coupled with, lifting device sensor system 100.

With continued reference to FIG. 1A, lifting device 120 includes anoperator cab 121 from which an operator manipulates controls to lift aload 104 with lifting arm 119. In some embodiments, a lifting devicethat is configured differently than lifting device 120 may not include acab, but may instead be operated with a handheld control box or in someother manner. Lifting device 120, in some embodiments, also includes oneor more of: an angle sensor/inclinometer 116 for measuring an angle oflifting arm 119; and a load cell 122 for monitoring the presence,absence, and or weight of a load 104 on load line 112. As illustrated inFIG. 1A, rigging 105 is used to couple load 104 with a hook 111 locatedat a distal end of load line 112.

In FIG. 1A, point 133 represents a three dimensional position of sensorunit 110 that has been determined by a GNSS receiver (e.g., GNSSreceiver 213A of FIG. 2A) disposed in. Point 134 represents a threedimensional position of or on load 104 that has been determined bysensor unit 110. In some embodiments, a GNSS receiver (e.g., GNSSreceiver 213A or 213B of FIG. 2A) of sensor unit 110 also determines anangular orientation 135 of point 133 or some other point on sensor unit110. Such an angular orientation identifies a swinging component ofsensor unit 110 that can occur as a result of sensor unit 110 beingcoupled with load line 112.

FIG. 1B shows an alternative coupling of sensor unit 110 of the sensorsystem 100 with a lifting device load line 112, in accordance with anembodiment. It is appreciated that FIG. 1B also illustrates only one ofone of several other techniques for coupling a hook 111 or attachmentpoint with a load line 112. In FIG. 1B, an end of load line 112 isfixedly coupled to lifting arm 119 at attachment point 171. Hook 111 iscoupled with a pulley 170 that moveably rides upon load line 112 and islocated at a gravity determined distal position (with respect to liftingarm 119) on load line 112.

FIG. 2A is a diagram of a selection of sensor unit components coupledwith a housing 201 of sensor unit 110, in accordance with an embodiment.As illustrated, in one embodiment, sensor unit 110 includes one or moreGNSS receivers 213, one or more power sources 217, one or more loadmonitors 214, and one or more wireless transceivers 215. In someembodiments sensor unit 110 may also include one or more additionalsensor unit components 216 (further described in FIG. 3). Thesecomponents of sensor unit 110 are communicatively and/or electricallycoupled with one another as required for performing functions of loadmonitoring, collision avoidance, and/or load hazard avoidance.

Housing 201 is configured to removably couple about a load line 112 of alifting device. As depicted, this comprises housing 201 coupling aboutload line 112 at a location between load hook 111 (or other type of loadattachment point in other embodiments) and the location where load line112 meets the lifting device. In depicted embodiments housing 201 issubstantially spherical, however other shapes are possible. Housing 201is comprised of a rigid or semi-rigid material or materials. In oneembodiment, all or a portion of housing 201 is made of an injectionmolded material such as high impact strength polycarbonate. In oneembodiment at least a portion of housing 201 is transparent to GNSSsatellite signals such that these signals can be received by GNSSreceiver(s) 213A, 213B, which are couple with housing 201 and securedinside housing 201. In some embodiments housing 201 comprises aplurality of sections (e.g., hemispheres 201A, 201B) that join, fasten,latch, or otherwise couple with one another to form housing 201 and toremovably couple about load line 112. Although two sections (hemispheres201A, 201B) are illustrated, some embodiments may include more. Asillustrated in FIG. 2A, hemispheres 201A and 201B removably couple withone another at joint 202.

Although housing 201 of sensor unit 110 is shown as being positionedabove hook 111 on load line 112, in some embodiments, some of all of thefunctions/components of a sensor unit 110 may be built into or housed inlifting hook 111 or similar load attachment point/mechanism located on adistal end/portion of load line 112. One example of such an embodiment,is depicted in FIG. 2D.

With continued reference to FIG. 2A, the removably couplablecharacteristic of housing 201 facilitates field mounting and removal ofsensor unit 110. In this manner, a construction company or crane rentalcompany, for example, can flexibly utilize sensor unit 110 with aplurality of different lifting devices by moving sensor unit 110 fromone lifting device load line to a load line of another lifting device.The removably couplable characteristic of housing 201 also facilitatesthe use of sensor unit 110 on lifting devices from a variety ofmanufacturers as no permanent mounting, hardwiring to the electricalsystem of the lifting device, or interfacing with the operating systemof the lifting device is required.

Load monitor 214 (214A, 214B illustrated) are coupled with housing 201and monitor a load 104 coupled with load line 112. This monitoringincludes monitoring a load position and/or a load orientation of load104. A load monitor may be a camera (e.g., a digital camera), aplurality of cameras, an ultrasonic sensor, a laser scanner, a bar codescanner, a radio frequency identification device transceiver, aninertial sensor (e.g., a gyroscope, accelerometer, mechanicalaccelerometer, an electro-mechanical accelerometer such as aMicro-Electro-Mechanical System (MEMS, etc.), or some combination ofthese. Load monitor(s) 214 typically face downward from sensor unit 110toward load hook 111 to attain a field of view 218 (218A, 218Billustrated) that encompasses at least a portion of load 104 andtypically some area in the surrounding vicinity of load 104. Through theuse of object identifiers 102 (as illustrated in FIG. 1A), a loadmonitor 214 can track and locate object(s) marked with one or moreobject identifiers 102 as such objects enter or depart from a field ofview 218. In some embodiments load monitor 214 performs ranging orpositioning through use of photogrammetry, laser scanning, and/orultrasonic measurement techniques in order to measure ranges to/andlocations of objects in a field of view 218. In some embodiments,ranges/positions of objects in a field of view 218 are determined as anoffset from a known three dimensional position of point 133 of sensorunit 110. In this manner, one or more positions with respect to a sensorunit 110 can be determined FIG. 1A illustrates one point 134, on load104, for which a position has been determined in this fashion. However,in some embodiments, additional ranges/positions can be determined. Forexample, the ranges/positions of object identifiers 102A, 102B, 102C,and or 102D, can be determined when they are within one or more fieldsof view 218. Inertial sensors are used in one embodiment to augment, orwork in conjunction with, the GNSS receivers 213 in determining theposition of sensor unit 110 in three dimensions. The use of inertialsensors in sensor unit 110 allows lifting device sensor system 100 tocontinue positioning functions for periods of time when the view of GNSSsatellites may be temporarily obstructed. The inertial sensors may alsoprovide motion detection of sensor unit 110 for the purpose ofinitiating a shut-down sequence of one or more components of liftingdevice sensor system 100 to preserve their battery life when it isdetermined that sensor unit 110 has not moved for a selected period oftime (e.g., five minutes, ten minutes, etc.). Alternatively, one or moreof GNSS receivers 213 can be used to determine that sensor unit 110 hasnot moved for a period of time for the purpose of shutting downcomponents of lifting device sensor system 100 to preserve their batterylife.

In one embodiment, a load monitor 214 also monitors for load relatedhazards in a vicinity of load 104. A load related hazard is an objectthat is at risk of impacting with or being impacted by load 104. Suchmonitoring can be accomplished using range or position information thatis determined regarding respective objects in one or more fields of view218. Such objects may or may not be labeled with object identifiers 102.In some embodiments, load monitor 214 additionally or alternativelyutilizes techniques such as facial recognition and/or infrared sensingto discern and monitor for persons 117 within a field of view 218.

It is appreciated that a field of view 218, and even overlapping fieldsof view (e.g., 218A, 218B, etc.), may have a blind spot beneath a load104. In one embodiment, a load related hazard that may be monitored foris the loss of view, in or near the blind spot, of an object identifier(e.g., 102C, 102D as illustrated in FIG. 1A) associated with a person117 or other object, or the loss of view of a person 117 that has beenidentified and monitored by other means.

Wireless transceiver 215 is coupled with housing 201. Wirelesstransceiver 215 may operate on any suitable wireless communicationprotocol including, but not limited to: WiFi, WiMAX, 802.11 family,cellular, two-way radio, and mesh networking. In one embodiment wirelesstransceiver 215 wirelessly provides information such as one or move of:load position (e.g., the position of point 134), load orientation,and/or a sensor unit position (e.g., the position of point 133) to adisplay unit 113 located apart from sensor unit 110. It is appreciatedthat other forms of information including, but not limited to, images,photos, video, lift plans, other object range/position information,object identification information, geofence information, collisionalerts, and load hazard alerts can be provided wirelessly provided to adisplay unit 113 located apart from sensor unit 110. In someembodiments, wireless transceiver 215 communicates with one or moreother sensor unit coupled with lifting devices that are withincommunication range. In some embodiments, wireless transceiver 215communicates with one or more sensors or devices that are coupled with alifting device, such sensors and devices include but are not limited to:a GNSS receiver (e.g., 107, 108, etc.), an angle sensor/inclinometer116, and a load cell 122. For example, by communicating with load cell122, load monitor 214 can receive information indicative of whether ornot lifting device 120 has taken on or released a load 104. In someembodiments, this will allow load monitor 214 or other component(s) ofsensor unit 110 to enter a low power energy conservation mode when aload 104 is not present in order to conserve power in power source(s)217.

With continued reference to FIG. 2A, one or more power sources 217A,217B are located inside housing 201. These power sources 217A, 217Bcouple with housing 201, and configured for providing electrical powerfor operating electrical components of sensor unit 110. These powersources 217 may comprise batteries, capacitors, or a combinationthereof. Additionally, as described further below, these power sources217 may be recharged by means of recharging contacts located on oraccessible through the exterior surface of housing 201; and may berecharged by a power source charger that is coupled with housing 201 (asa part of sensor unit 110) and generates electrical power (e.g., throughmotion of sensor unit 110, through solar power production, or by othersuitable power generation process).

FIG. 2B illustrates a selection of features of a lifting device sensorunit 110, in accordance with various embodiments. The featuresillustrated in FIG. 2B are located on or are accessible via the externalsurface of housing 201. This selection of features includes: a soundemitting device 251 (e.g., a speaker, siren, horn, or the like); a lightemitting device 252 (e.g., a light bulb, strobe, light emitting diode,or the like); an access hatch 253; recharge contacts 254; and/or aprotective bumper 255. Some, all, or none of these features may beincluded in embodiments of sensor unit 110. In one embodiment, lightemitting device 252 comprises an array of status indicator lights suchas Light Emitting Diodes (LEDs) which can be used to convey statusinformation to an operator of lifting device 120.

In one embodiment, access hatch 253 provides easy access to componentsthat are located in an internal portion of sensor unit 110. In someembodiments, access hatch 253 is a power source access hatch thatfacilitates access to power source(s) 217, to facilitate recharge,removal, and/or replacement of power source(s) 217 while sensor unit 110remains coupled with load line 112. This allows some routine maintenanceor internal access without requiring removal of sensor unit 110 fromload line 112 or decoupling of housing portions 201A and 201B from oneanother.

Recharge contacts 254 facilitate recharge of power source(s) 217 withoutrequiring removal of sensor unit 110 from load line 112 or decoupling ofhousing portions 201A and 201B from one another. For example, a personmay attach charging leads to recharge contacts 254, or charging leadsmay automatically engage with recharge contacts 254 when sensor unit 110is placed in a docked state. With reference to lifting device 120, inone embodiment, a docked state may be achieved by raising sensor unit110 until it makes encounters a stop at lifting arm 119 where a dock orcharging leads may reside. In other embodiments, when used withdifferent types of lifting devices, a docked state may not be achievableor may be achieved in a different manner.

Protective bumper 255 extends from a portion of the external surface ofhousing 201 and provides a limited amount of impact protection forsensor unit 110. In some embodiments, protective bumper 255 may serve anadditional purpose of securing or assisting in securing closure ofportions (e.g., 201A, 201B) of housing 201. Protective bumper 255 may beslidably emplaced on housing 201 and held in place by friction and/orelastive force. Protective bumper 255 may also be latched or secured inplace on housing 201.

FIG. 2C illustrates an example load line positioner 261 coupled with ahousing 201 of sensor unit 110, in accordance with an embodiment. In oneembodiment, load line positioner 261 comprises an arrangement of aplurality of pinch rollers/motors 261A, 261B, 261C to both hold sensorunit 110 in a particular place on load line 112 and to facilitatecontrollable and adjustable movement and positioning of sensor unit 110along load line 112 (as indicated by the bi-directional arrow). Suchmovement, in one embodiment is controlled by position control 320 (FIG.3) and may occur automatically in accordance with predefined criteria orin accordance with an input wirelessly received by sensor unit 110 (suchas from a display unit 113 in response to a user input).

Movement of sensor unit 110 along load line 112 allows load monitor(s)114 to monitor load 104 and take measurements from different locations.This can assist in photogrammetry and in other techniques used fordetermining range and/or position of objects in field of view(s) 218.Moreover, in performance of some lifts, it may be advantageous to movethe sensor unit 110 in order for it to maintain reception of GNSSsignals that would otherwise be shielded or blocked by objects in thelift area. Additionally, loads of large size may require the sensor unit110 to be moved upward so that larger field(s) of view 218 around load104 can be achieved than would be possible with sensor unit 110 incloser proximity to load 104. For example, it may be easy to get a fieldof view on sides of an I-beam with the sensor unit 110 located near theI-beam, but difficult to get a field on sides of a large panel, pallet,or container that block portions of the field of view from the sameposition of sensor unit 110. Additional movement of sensor unit 110 mayoccur in situations where the lifting device 120 uses a pulley typearrangement for securing hook 111 to load line 112 (as illustrated inFIG. 1B).

FIG. 2D illustrates an example sensor unit 110 coupled with a hook block111, in accordance with various embodiments. As in FIGS. 2A and 2D,sensor unit 110 includes a housing 201 with which or within which, thevarious components and sensors of sensor unit 110 may be coupled. It isappreciated that one or more of the various features described inconjunction with FIG. 2A and FIG. 2B may be included in the sensor unitand housing thereof which are depicted in FIG. 2D. Although depicted asspherical, housing 201 of FIG. 2D, may be of other shapes. Additionally,although depicted as being disposed in the midst of load hook 111,sensor unit 110 and its housing 201 may be disposed between load line112 and hook 111, in some embodiments or fully integrated within hook111. The combination of hook 111 and sensor 110, as depicted in FIG. 2D,is one example of a hook block sensor assembly (e.g., hook block sensorassembly 1101, which is described in conjunction with FIG. 11). Thoughnot illustrated in FIG. 2D, in some embodiments, hook 111 may beintegrated with one or more pulleys such that cable 112 may be coupledwith two or more points of a lifting arm 119 (see e.g., FIG. 1B, for onesuch example).

FIG. 3 is a block diagram of additional lifting device sensor unitcomponents 216 that may be variously included in a lifting device sensorunit 110, according to one or more embodiments. These additional sensorunit components may include one or more of a lift plan generator 305, acollision monitor 310, an avoidance action initiator 315, a positioncontrol 320, and a power source charger 325.

Lift plan generator 305 generates a lift plan for efficiently liftingand/or safely lifting a load 104 to a destination associated with theload. Following such a lift plan, rather than having an operator“eyeball” a lift from scratch with no lift plan can reduce accidents andin many cases speed lifting, thus improving productivity. In oneembodiment, lift plan generator 305 utilizes identified informationregarding a load to ascertain where its destination is on a job site.Other information such as a destination orientation of a load 104 may beascertained. Such information can be discerned based on one or moreobject identifiers 102 that may be coupled with a load 104 and mayinclude this information, such as in an RFID memory or may provide aidentifier associated with the load which can be used for looking up oraccessing such load destination information from a job site schematic orvirtual plan. Lift plan generator 305 may additionally or alternativelytake into account known (e.g., mapped such as in a virtual site plan orpreviously recognized by sensor unit 110) objects and hazards which arein the vicinity of the lift, such that these hazards are safely avoidedin the generated lift plan. In this fashion, based on the virtual planof a site and/or objects that load monitor 214 has mapped, the lift planis generated such that an efficient path is outlined which does allowsthe load to avoid known hazards between the start and destination of thelift. In one embodiment wireless transceiver 215 provides this lift planto a display unit 113 for display to a user during the lift. Lift plangenerator 305 can also be used when multiple lifting devices 120 areused to lift and/or move a single shared load. In one embodiment, aseparate lift plan generator 305 is implemented on each of the liftingdevices 120 that are coordinating their efforts to lift and/or move asingle shared load and generates commands to control the operation ofits respective lifting device 120 such that the single shared load canbe lifted and/or moved safely and efficiently. In one embodiment,communication between sensor unit 110 can be sent to multiple displayunits 113A and 113B to coordinate implementation of lifting and/ormoving of a single shared load, or communication between multiple sensorunits 110 can be sent to a single display unit 113A or 113B tocoordinate implementation of lifting and/or moving of a single sharedload. Similarly, communication between multiple sensor units 110 can besent to multiple display units 113A and 113B to coordinateimplementation of lifting and/or moving of a single shared load.

FIG. 4 illustrates a display of an example lift plan 400 that has beengenerated by a lifting device sensor unit 110, according to anembodiment. Lift plan 400 includes a top plan view 410 and a sideelevation view 420 of the lift path of load 104 from an initial location401 to a destination location 402. It is appreciated that, in someembodiments, additional or different views of the lift path of a loadmay be generated by lift plan generator 305. It is also appreciatedthat, in some embodiments, all or a portion of lift plan 400 may bedisplayed in conjunction with an image or virtual image of theenvironment through which a load will be lifted.

Referring again to FIG. 3, collision monitor 310 monitors for collisionrelated hazards in a vicinity of a lifting device to which sensor unit110 is coupled. In one embodiment, this collision monitoring functionrelies on position information from one or more other sensor unitscoupled that are coupled with other lifting devices. In one embodiment,collision monitor generates a geofence (a virtual barrier based uponpositional coordinates) that surrounds the lifting device to which it iscoupled. This geofence can be generated in several ways. One embodimentcomprises establishing a circular geofences at a preset radius from aposition of point 133 of sensor unit 110. This radius may be set whensensor unit 110 is initially coupled with a load line 112. Anotherembodiment comprises using a position (e.g., the position of point 133)that is associated with a position of sensor unit 110 as a radius fordrawing a circular geofence around a position (e.g., the position ofpoint 143) on the body of lifting device 120. In either case, thegeofence may be re-generated by collision monitor 310 at regularintervals or as positions used in the calculation of the geofencechanges.

Collision monitor 310 stores the generated geofence for lifting device120 and then generates or utilizes similar geofences for other liftingdevices in the area to which other sensor units 110 are coupled.Collision monitor 310 then monitors the geofences for occurrence ofcollision related hazard such as intersection of the geofences orencroachment of the position of a sensor unit or body of one liftingdevice across the border of a geofence associated with a differentlifting device. In one embodiment, wireless transceiver 215 providesgeofence information generated or stored in collision monitor 310 to adisplay unit 113.

FIG. 5 illustrates a display of example lifting device geofenceinformation 500 that has been generated by one or more lifting devicesensor units 110, according to an embodiment. A geofence 510 isillustrated for lifting device 120. A second geofence 520 is illustratedfor a second lifting device. Collision monitor 310 has generatedgeofence 510 as a circle about the position of point 143, with a radiusestablished by the position of point 133 (see FIG. 1A). Geofence 520 hasbeen generated in a similar manner as a circle about the position ofpoint 521 (located on the body of a second lifting device), with aradius established by the position of point 522 (located on a sensorunit coupled with the load line of the second lifting device). Thistechnique for generating geofences is acceptable for certain liftingdevices such as boom cranes, when a sensor unit will be locatedsubstantially on a gravity vector beneath a boom tip. Other techniques,to include the use of buffer zones can utilized in other situations.

In one embodiment, collision monitor 310 monitors for a collision hazardsuch as an intersection 540 of geofences 510 and 520 or an incursion oranticipated incursion (based on direction and speed) of a knownposition, such as the position of point 133 with a point 541, 542 on thecircumference of geofence 520 or the similar incursion of the positionof point 522 with a point 541, 542 on the circumference of geofence 510.In one embodiment, when a collision hazard has been monitored bycollision monitor 310, information regarding the occurrence of thecollision hazard is provided to avoidance action initiator 315.

An avoidance action initiator 315 initiates at least one hazardavoidance action in response to a monitored occurrence of a collisionrelated hazard. In various embodiments, among other actions, this cancomprise initiating one or more actions such as causing a warning tosound from sound emitting device 251, causing illumination of anindicator of light emitting device 252, and/or causing a collisionwarning to be transmitted to a display unit 113. It is appreciated thatavoidance action initiator 315 may initiate one or more similar actionsin response to a monitored occurrence of a load hazard condition beingindicated by load monitor 314. In various embodiments, among otheractions, this can comprise one or more of causing a warning to soundfrom sound emitting device 251, causing illumination of an indicator oflight emitting device 252, and/or causing a load hazard warning to betransmitted to a display unit 113. In one embodiment, avoidance actioninitiator 315 may generate commands which automatically initiatesuspension of movement of load 104 to prevent a collision with anotherobject. When it is determined that load 104 can again be moved safely, asafety code can be entered (e.g., using display unit 113A or 113B).

Position control 320 generates positioning commands, such as motorcontrol signals for controlling the operation of load line positioner261 or components thereof.

Power source charger 325 generating a charge for charging powersource(s) 217. In various embodiments power source charger 325 comprisesone or more of a solar panel and/or a motion induced power generator(operating in a similar fashion to the rotor of a self-winding watch).It is appreciated that even a small amount of power generated by powersource charger 325 will extend the operational duration of powersource(s) 217 and thus reduce down time of sensor unit 110.

In some embodiments, sensor unit(s) 110 and/or other portions of sensorsystem 100 act as reporting sources, which report information to anasset management system. Such an asset management system may becentralized or decentralized and may be located on or off of aconstruction site at which one or more reporting sources are located.The reporting sources report information regarding constructionequipment assets to which they are coupled. Such information may includeposition information, operational information, and/or time of operationinformation. Such an asset management system may comprise a computersystem (e.g., computer system 1000) such as a server computer and/or adatabase which are used for generating reports, warnings, and the liketo be based upon reported information which may include one or more of(but is not limited to) location of operation of a constructionequipment asset, time of day of operation of a construction equipmentasset, interaction of a construction equipment asset with respect to oneor more another construction equipment assets, interaction of aconstruction equipment asset with respect to a geofence, and/orcompliance or non-compliance with a rule or condition of use associatedwith a construction equipment asset. Typically such a computer systemand/or database will be located remotely from a sensor unit 110 and asensor system 100.

In some embodiments, sensor unit(s) 110 and/or other portions of sensorsystem 100 act as reporting sources for reporting information to alifting device load monitoring system, lifting device collisionavoidance system, lifting device load hazard avoidance system, and/or avirtual reality system. Such a load monitoring system, collisionavoidance system, load hazard avoidance system, and/or a virtual realitysystem may be centralized or decentralized and may be located on or offof a construction site at which one or more reporting sources arelocated. Such a load monitoring system, collision avoidance system, loadhazard avoidance system, and/or a virtual reality system may comprise orbe implemented with a computer system (e.g., computer system 1000) orsome variation thereof. Typically, such a computer system will belocated remotely from a sensor unit 110 and a sensor system 100. In someembodiments, one or more of object identification, lift plan generation,collision avoidance monitoring, load hazard monitoring, geofencegeneration, avoidance action initiation, and/or other functionsdescribed above with respect to sensor system 100 and/or sensor unit 110may be handled by a collision avoidance and/or virtual reality system.Such functions may be implemented based in whole or in part oninformation reported by one or more sensor systems 100 or sensor units110.

Example Methods of Use

With reference to FIGS. 6, 7, and 8, flow diagrams 600, 700, and 800illustrate example procedures used by various embodiments. Flow diagrams600, 700, and 800 include processes and operations that, in variousembodiments, are carried out by one or more processors (e.g.,processor(s) 1006 of FIG. 10) under the control of computer-readable andcomputer-executable instructions. The computer-readable andcomputer-executable instructions reside, for example, in tangible datastorage features such as volatile memory, non-volatile memory, and/or adata storage unit (see e.g., 1008, 1010, and 1012 of FIG. 10). Thecomputer-readable and computer-executable instructions can also resideon any tangible computer readable media such as a hard disk drive,floppy disk, magnetic tape, Compact Disc, Digital Versatile Disc, andthe like. The computer-readable and computer-executable instructions,which may reside on computer readable media, are used to control oroperate in conjunction with, for example, one or more components ofsensor unit 110 and/or and or one or more processors 1006.

Although specific procedures are disclosed in flow diagrams 600, 700,and 800 such procedures are examples. That is, embodiments are wellsuited to performing various other operations or variations of theoperations recited in the processes of flow diagrams 600, 700, and 800.Likewise, in some embodiments, the operations in flow diagrams 600, 700,and 800 may be performed in an order different than presented, not allof the operations described in one or more of these flow diagrams may beperformed, and/or one or more additional operation may be added.

Example Method of Monitoring a Lifting Device Load

FIG. 6 is a flow diagram 600 of an example method of monitoring alifting device load, in accordance with an embodiment. Reference will bemade to FIGS. 1A and 2A to facilitate the explanation of the operationsof the method of flow diagram 600. In one embodiment, the method of flowdiagram 600 describes a use of sensor unit 110 and/or sensor system 100,while coupled with a lifting device, such as lifting device 120.

At operation 610, in one embodiment, a three dimensional position isdetermined for a point of a sensor unit 110 that is coupled with a loadline 112 of a lifting device 120. This position determining is performedby at least a first GNSS receiver 213 that is coupled with a housing 201of sensor unit 110. For example, this can comprise GNSS receiver 213Adetermining a three dimensional position of point 133 of sensor unit110. This can further comprise GNSS receiver 213A (assuming it is a dualaxis GNSS receiver with multiple antennas) or GNSS receiver 213B furtherdetermining an angular orientation of sensor unit 110.

At operation 620, in one embodiment, load position and a loadorientation of a load 104 are monitored. The monitored load 104 iscoupled with the load line 112 of the lifting device 120. In oneembodiment, this monitoring of the load is performed by load monitor 214in the manner that has previously been described herein.

At operation 630, in one embodiment, information is wirelessly providedfrom the sensor unit to a display unit located apart from the sensorunit. The information includes one or more of the load position, theload orientation, and the sensor unit position. The information may alsoinclude position, ranging, laser scanner information, bar codeinformation, RFID information, load related hazard information, or imageinformation related to objects monitored in the field of view of loadmonitor(s) 214. Wireless transceiver 215 transmits or provides access ofthis information. This can comprise wirelessly providing the informationfor display on a hand-holdable unit (e.g., on display unit 113B) fordisplay in an operator cab of the lifting device (e.g., on display unit113A) or for transmission to another sensor unit 110 or other device orsystem.

Example Method of Lifting Device Collision Avoidance

FIG. 7 is a flow diagram 700 of an example method of lifting devicecollision avoidance, in accordance with an embodiment. Reference will bemade to FIGS. 1A, 2A, 3, and 5 to facilitate the explanation of theoperations of the method of flow diagram 700. In one embodiment, themethod of flow diagram 700 describes a use of sensor unit 110 (referredto as a lifting device collision avoidance unit) and/or sensor system100, while coupled with a lifting device, such as lifting device 120.

At operation 710, in one embodiment, a three dimensional position isdetermined for a point of a collision avoidance sensor unit 110 that iscoupled with a load line 112 of a lifting device 120. This positiondetermining is performed by at least a first GNSS receiver 213 that iscoupled with a housing 201 of collision avoidance sensor unit 110. Forexample, this can comprise GNSS receiver 213A determining a threedimensional position of point 133 of collision avoidance sensor unit110. This can further comprise GNSS receiver 213A (assuming it is a dualaxis GNSS receiver with multiple antennas) or GNSS receiver 213B furtherdetermining an angular orientation of collision avoidance sensor unit110.

At operation 720, in one embodiment, a geofence is generated for thefirst lifting device 120. The geofence is generated based at least inpart on the collision avoidance sensor unit position that has beendetermined. In one embodiment, the geofence is generated by collisionmonitor 310 in the manner that has been previously described herein.

At operation 730, in one embodiment, a collision related hazard ismonitored for occurrence. Occurrence of a collision related hazard isindicated by encroachment between the first geofence and a secondgeofence that is associated with a second lifting device. In oneembodiment, collision monitor 310 monitors for occurrence of a collisionrelated hazard in the manner previously described herein. The secondgeofence may be generated by collision monitor 310 based on positioninformation accessed from a second collision avoidance sensor unit thatis coupled with the second lifting device, or the second geofence may bereceived from the second collision avoidance sensor unit.

At operation 740, in one embodiment, at least one collision hazardavoidance action is initiated in response to a monitored occurrence of acollision related hazard. In one embodiment, this comprises avoidanceaction initiator 315 initiating an avoidance action in response tocollision monitor 310 monitoring an occurrence of collision relatedhazard. As previously described this can comprise avoidance actioninitiator 315 causing wireless transceiver 215 to wirelessly provide acollision alert for display on a display unit 113 that is located apartfrom collision avoidance sensor unit 110; causing a warning such as asiren, tone, or horn to sound; and/or or causing an indicator such as alight or strobe to illuminate.

At operation 750, in one embodiment, method of flow diagram 700additionally comprises wirelessly providing the first geofence and thesecond geofence from the collision avoidance sensor unit 110 to adisplay unit 113 located apart from the collision avoidance sensor unit110. FIG. 5 shows an example of such information displayed on displayunit 113. It is appreciated that more that two geofences may be providedfor display in other embodiments. It is also appreciated that thegeofences may be displayed in conjunction with images or virtual imagesof the working area in and surrounding the geofences.

Example Method of Lifting Device Load Hazard Avoidance

FIG. 8 is a flow diagram 800 of an example method of lifting device loadhazard avoidance, in accordance with an embodiment. Reference will bemade to FIGS. 1A, 2A, and 3 to facilitate the explanation of theoperations of the method of flow diagram 800. In one embodiment, themethod of flow diagram 800 describes a use of sensor unit 110 (referredto as a lifting device load hazard avoidance unit) and/or sensor system100, while coupled with a lifting device, such as lifting device 120.

At operation 810, in one embodiment, a three dimensional position isdetermined for a point of a load hazard avoidance sensor unit 110 thatis coupled with a load line 112 of a lifting device 120. This positiondetermining is performed by at least a first GNSS receiver 213 that iscoupled with a housing 201 of load hazard avoidance sensor unit 110. Forexample, this can comprise GNSS receiver 213A determining a threedimensional position of point 133 of load hazard avoidance sensor unit110. This can further comprise GNSS receiver 213A (assuming it is a dualaxis GNSS receiver with multiple antennas) or GNSS receiver 213B furtherdetermining an angular orientation of load hazard avoidance sensor unit110.

At operation 820, in one embodiment, a load related hazard in a vicinityof a load 104 is monitored for. The load 104 is coupled with load line112 of lifting device 120. In one embodiment, the monitoring performedby load monitor(s) 214 in one or more of the manners previouslydescribed herein. This includes monitoring for an imminent or potentialcollision between load 104 and an object in the vicinity of load 104.This also includes monitoring for loss of visibility of a person 117beneath load 104.

At operation 830, in one embodiment, at least one load related hazardavoidance action is initiated in response to a monitored occurrence of aload related hazard. In one embodiment, this comprises avoidance actioninitiator 315 initiating an avoidance action in response to loadmonitor(s) 114 monitoring an occurrence of load related hazard. Aspreviously described this can comprise avoidance action initiator 315causing wireless transceiver 215 to wirelessly provide a load hazardalert for display on a display unit 113 that is located apart fromcollision avoidance sensor unit 110; causing a warning such as a siren,tone, or horn to sound; and/or or causing an indicator such as a lightor strobe to illuminate.

Example GNSS Receiver

FIG. 9, shows an example GNSS receiver 900, according to one embodimentwhich may be utilized all or in part one or more of GNSS receivers 213A,213B, 107, and/or 108. It is appreciated that different types orvariations of GNSS receivers may also be suitable for use in theembodiments described herein. In FIG. 9, received L1 and L2 signals aregenerated by at least one GPS satellite. Each GPS satellite generatesdifferent signal L1 and L2 signals and they are processed by differentdigital channel processors 952 which operate in the same way as oneanother. FIG. 9 shows GPS signals (L1=1575.42 MHz, L2=1227.60 MHz)entering GPS receiver 900 through a dual frequency antenna 932. Antenna932 may be a magnetically mountable model commercially available fromTrimble Navigation of Sunnyvale, Calif. Master oscillator 948 providesthe reference oscillator which drives all other clocks in the system.Frequency synthesizer 938 takes the output of master oscillator 948 andgenerates important clock and local oscillator frequencies usedthroughout the system. For example, in one embodiment frequencysynthesizer 938 generates several timing signals such as a 1st (localoscillator) signal LO1 at 1400 MHz, a 2nd local oscillator signal LO2 at175 MHz, an SCLK (sampling clock) signal at 25 MHz, and a MSEC(millisecond) signal used by the system as a measurement of localreference time.

A filter/LNA (Low Noise Amplifier) 934 performs filtering and low noiseamplification of both L1 and L2 signals. The noise figure of GPSreceiver 900 is dictated by the performance of the filter/LNAcombination. The downconvertor 936 mixes both L1 and L2 signals infrequency down to approximately 175 MHz and outputs the analogue L1 andL2 signals into an IF (intermediate frequency) processor 950. IFprocessor 950 takes the analog L1 and L2 signals at approximately 175MHz and converts them into digitally sampled L1 and L2 inphase (L1 I andL2 I) and quadrature signals (L1 Q and L2 Q) at carrier frequencies 420KHz for L1 and at 2.6 MHz for L2 signals respectively.

At least one digital channel processor 952 inputs the digitally sampledL1 and L2 inphase and quadrature signals. All digital channel processors952 are typically are identical by design and typically operate onidentical input samples. Each digital channel processor 952 is designedto digitally track the L1 and L2 signals produced by one satellite bytracking code and carrier signals and to from code and carrier phasemeasurements in conjunction with the microprocessor system 954. Onedigital channel processor 952 is capable of tracking one satellite inboth L1 and L2 channels. Microprocessor system 954 is a general purposecomputing device (such as computer system 1000 of FIG. 10) whichfacilitates tracking and measurements processes, providing pseudorangeand carrier phase measurements for a navigation processor 958. In oneembodiment, microprocessor system 954 provides signals to control theoperation of one or more digital channel processors 952. Navigationprocessor 958 performs the higher level function of combiningmeasurements in such a way as to produce position, velocity and timeinformation for the differential and surveying functions. Storage 960 iscoupled with navigation processor 958 and microprocessor system 954. Itis appreciated that storage 960 may comprise a volatile or non-volatilestorage such as a RAM or ROM, or some other computer readable memorydevice or media. In one rover receiver embodiment, navigation processor958 performs one or more of the methods of position correction.

In some embodiments, microprocessor 954 and/or navigation processor 958receive additional inputs for use in refining position informationdetermined by GPS receiver 900. In some embodiments, for example,corrections information is received and utilized. Such correctionsinformation can include differential GPS corrections, RTK corrections,and wide area augmentation system (WAAS) corrections.

Example Computer System Environment

With reference now to FIG. 10, all or portions of some embodimentsdescribed herein are composed of computer-readable andcomputer-executable instructions that reside, for example, incomputer-usable/computer-readable storage media of a computer system.That is, FIG. 10 illustrates one example of a type of computer (computersystem 1000) that can be used in accordance with or to implement variousembodiments which are discussed herein. It is appreciated that computersystem 1000 of FIG. 10 is only an example and that embodiments asdescribed herein can operate on or within a number of different computersystems including, but not limited to, general purpose networkedcomputer systems, embedded computer systems, server devices, variousintermediate devices/nodes, stand alone computer systems, handheldcomputer systems, multi-media devices, and the like. Computer system1000 of FIG. 10 is well adapted to having peripheral computer-readablestorage media 1002 such as, for example, a floppy disk, a compact disc,digital versatile disc, universal serial bus “thumb” drive, removablememory card, and the like coupled thereto.

System 1000 of FIG. 10 includes an address/data bus 1004 forcommunicating information, and a processor 1006A coupled to bus 1004 forprocessing information and instructions. As depicted in FIG. 10, system1000 is also well suited to a multi-processor environment in which aplurality of processors 1006A, 1006B, and 1006C are present. Conversely,system 1000 is also well suited to having a single processor such as,for example, processor 1006A. Processors 1006A, 1006B, and 1006C may beany of various types of microprocessors. System 1000 also includes datastorage features such as a computer usable volatile memory 1008, e.g.,random access memory (RAM), coupled to bus 1004 for storing informationand instructions for processors 1006A, 1006B, and 1006C. System 1000also includes computer usable non-volatile memory 1010, e.g., read onlymemory (ROM), coupled to bus 1004 for storing static information andinstructions for processors 1006A, 1006B, and 1006C. Also present insystem 1000 is a data storage unit 1012 (e.g., a magnetic or opticaldisk and disk drive) coupled to bus 1004 for storing information andinstructions. System 1000 also includes an optional alphanumeric inputdevice 1014 including alphanumeric and function keys coupled to bus 1004for communicating information and command selections to processor 1006Aor processors 1006A, 1006B, and 1006C. System 1000 also includes anoptional cursor control device 1016 coupled to bus 1004 forcommunicating user input information and command selections to processor1006A or processors 1006A, 1006B, and 1006C. In one embodiment, system1000 also includes an optional display device 1018 coupled to bus 1004for displaying information.

Referring still to FIG. 10, optional display device 1018 of FIG. 10 maybe a liquid crystal device, cathode ray tube, plasma display device orother display device suitable for creating graphic images andalphanumeric characters recognizable to a user. Optional cursor controldevice 1016 allows the computer user to dynamically signal the movementof a visible symbol (cursor) on a display screen of display device 1018and indicate user selections of selectable items displayed on displaydevice 1018. Many implementations of cursor control device 1016 areknown in the art including a trackball, mouse, touch pad, joystick orspecial keys on alphanumeric input device 1014 capable of signalingmovement of a given direction or manner of displacement. Alternatively,it will be appreciated that a cursor can be directed and/or activatedvia input from alphanumeric input device 1014 using special keys and keysequence commands System 1000 is also well suited to having a cursordirected by other means such as, for example, voice commands. System1000 also includes an I/O device 1020 for coupling system 1000 withexternal entities. For example, in one embodiment, I/O device 1020 is amodem for enabling wired or wireless communications between system 1000and an external network such as, but not limited to, the Internet.

Referring still to FIG. 10, various other components are depicted forsystem 1000. Specifically, when present, an operating system 1022,applications 1024, modules 1026, and data 1028 are shown as typicallyresiding in one or some combination of computer usable volatile memory1008 (e.g., RAM), computer usable non-volatile memory 1010 (e.g., ROM),and data storage unit 1012. In some embodiments, all or portions ofvarious embodiments described herein are stored, for example, as anapplication 1024 and/or module 1026 in memory locations within RAM 1008,computer-readable storage media within data storage unit 1012,peripheral computer-readable storage media 1002, and/or other tangiblecomputer readable storage media.

Ad-Hoc Wireless Communication Network

FIG. 11 is a block diagram of an example ad-hoc wireless personal areanetwork 1100 in accordance with one or more embodiments. In FIG. 11, ahook block sensor assembly 1101 is communicatively coupled with displayunit 113 via wireless connection 1111. As described above, in oneembodiment, sensor unit 110 may be built into or housed in lifting hook111, or a similar load attachment point/mechanism, located on a distalend/portion of load line 112. For the purpose of brevity, acomprehensive illustration of components of sensor unit 110 which areimplemented as hook block sensor assembly 1101 are not shown in FIGS. 11and 12. However, it is understood that various features and componentsof sensor unit 110 as described above are combined in implementations ofhook block sensor assembly 1101. In FIG. 11, hook block sensor assembly1101 comprises a GNSS antenna 1102 and one or more GNSS receivers 1103.Hook block sensor assembly 1101 further comprises a power supply 1104for supplying power to hook block sensor assembly 1101. It is noted thatpower supply 1104 can comprise batteries and/or a connection to vehiclesupplied power.

A radio transceiver 1105 and wireless antenna 1106 provide wirelesscommunication between hook block sensor assembly 1101 and display unit113 as indicated by 1111. Hook block sensor assembly 1101 furthercomprises one or more sensor units 1107 which are implemented toaccomplish load monitoring and/or as described above with reference toload monitors 214. Sensor units 1107 can further be used for lift planimplementation, position control, collision monitoring, and initiatingavoidance actions as discussed above with reference to sensor unitcomponents 216 of FIG. 2A. These components of hook block sensorassembly 1101 are communicatively and/or electrically coupled with oneanother as required for performing functions of load monitoring,collision avoidance, and/or load hazard avoidance as described above.

In accordance with various embodiments, the components of hook blocksensor assembly 1101 are housed within a housing 201 (see e.g., FIG.2D). In one embodiment, housing 201 is coupled with hook 111 (see e.g.,FIG. 2D) and one or more of the components of hook block sensor assembly1101 described above in FIGS. 2A, 2B, and 3 are coupled with housing201. Alternatively, the components of hook block sensor assembly 1101may be coupled with hook 111 and enclosed by housing 201. It is furthernoted that other components of sensor unit 110 (e.g., sound emittingdevice 251, light emitting device 252, access hatch 253, rechargecontacts 254, and/or protective bumper 255) may be included in housing201 in accordance with various embodiments.

As discussed above, display unit 113 may be a dedicated display with awireless transceiver or may be part of an electronic device such assmart phone, netbook, notebook computer, tablet computer, or the like.In the embodiment of FIG. 11, display unit 113 is removeably coupledwith a docking station 1108 which provides connection to a power source(not shown) and a communication connection with L1 GNSS antenna 1110. Inaccordance with various embodiments, display device 1160 may be a liquidcrystal device, cathode ray tube, or a touch screen assembly configuredto detect the touch or proximity of a user's finger, or other inputdevice, at or near the surface of display device 1160 and to communicatesuch an event to a processor (e.g., processors 1006A, 1006B, and/or1006C of FIG. 10). Display unit 113 further comprises batteries 1161 forproviding power to display unit 113 when it is de-coupled from dockingstation 1108.

Display unit 113 further comprises one or more wireless radiotransceivers 1162 and wireless antenna 1163 for wirelessly communicatingwith other components of ad-hoc wireless personal area network 1100. Inthe embodiment of FIG. 11, display unit 113 comprises a GNSS receiver1164 and GNSS antenna 1165 configured for receiving satellite navigationsignals and for determining the position of display unit 113. As shownin FIG. 11, display unit 113 is communicatively coupled with L1 GNSSantenna 1110 which is used to receive satellite navigation signals whendisplay unit 113 is coupled with docking station 1108. This to improvethe reception of satellite navigation signals which may be blocked ordegraded when display unit 113 is located within cab 121. An example ofa commercially available model of display unit 113 is the Yuma® computerfrom Trimble Navigation of Sunnyvale, Calif.

In accordance with various embodiments, one or more of wireless radiotransceivers 1105 and 1162 may operate on any suitable wirelesscommunication protocol including, but not limited to: WiFi, WiMAX, WWAN,implementations of the IEEE 802.11 specification, cellular, two-wayradio, satellite-based cellular (e.g., via the Inmarsat or Iridiumcommunication networks), mesh networking, implementations of the IEEE802.15.4 specification for personal area networks, and implementationsof the Bluetooth® standard. Personal area networks refer to short-range,and often low-data-rate, wireless communications networks. In accordancewith embodiments of the present technology, components of ad-hocwireless personal area network 1100 are configured for automaticdetection of other components and for automatically establishingwireless communications. In one embodiment, display unit 113 comprises afirst wireless radio transceiver 1162 for communicating with othercomponents of ad-hoc wireless personal area network 1100 and one or morewireless radio transceivers 1162 for wirelessly communicating outside ofad-hoc wireless personal area network 1100.

FIG. 12 is a block diagram of an example ad-hoc wireless personal areanetwork 1100 in accordance with one or more embodiments. In FIG. 12,ad-hoc wireless personal area network 1100 comprises hook block sensorassembly 1101 and display unit 113 as described above with reference toFIG. 11. In FIG. 12, ad-hoc wireless personal area network 1100 furthercomprises GNSS antenna unit 1120. In the embodiment of FIG. 12, GNSSantenna unit 1120 comprises a GNSS antenna 1121 and GNSS receiver 1122for receiving satellite navigation signals and for determining theposition of GNSS antenna unit 1120. GNSS antenna unit 1120 furthercomprises one or more wireless radio transceivers 1123 and wirelessantenna 1124 for providing wireless communication with display unit 113as indicated by 1112. In accordance with various embodiments, wirelessradio transceiver 1123 may operate on any suitable wirelesscommunication protocol including, but not limited to: WiFi, WiMAX, WWAN,implementations of the IEEE 802.11 specification, cellular, two-wayradio, satellite-based cellular (e.g., via the Inmarsat or Iridiumcommunication networks), mesh networking, implementations of the IEEE802.15.4 specification for personal area networks, and implementationsof the Bluetooth® standard. An example of a commercially available modelof GNSS antenna unit is the SPS 882 Smart GPS Antenna from TrimbleNavigation of Sunnyvale, Calif. In one embodiment, GNSS antenna unit1120 is mounted at the rear of lifting device 120 as shown by globalnavigation satellite receiver 108 of FIG. 1A.

In operation, hook block sensor assembly 1101, display unit 113, andGNSS antenna unit 1120 are configured to implement an ad-hoc wirelesspersonal area network to assist in or accomplish one or more ofefficient load delivery, load monitoring, collision avoidance, and loadhazard avoidance as described above. In one embodiment, hook blocksensor assembly 1101, display unit 113, and GNSS antenna unit 1120 areconfigured to initiate an automatic discovery process in whichcomponents of ad-hoc wireless personal area network 1100 detect eachother by exchanging messages without the necessity of user initiationand/or intervention. Additionally, in one embodiment hook block sensorassembly 1101, display unit 113, and GNSS antenna unit 1120 areconfigured to automatically initiate processes to assist in oraccomplish one or more of efficient load delivery, load monitoring,collision avoidance, and load hazard avoidance such as determining theposition of hook block sensor assembly 1101, display unit 113, and/orload 104. Furthermore, in one embodiment display unit 113 is configuredto send and receive data outside of ad-hoc wireless personal areanetwork 1100. Thus, display unit can be used to receive updates,correction data for position determination, and other instructions forimplementing a plan at a site. Additionally, display unit 113 can beused for storing, forwarding, and reporting data used in site monitoringor other purposes.

FIG. 13 is a block diagram of an example communication network 1300 inaccordance with one or more embodiments. In FIG. 13, one or more ad-hocwireless personal area networks 1100 are communicatively coupled withlocal area wireless repeater 1302, cellular/wireless repeater 1303, andlocal reference station 1304 via wireless connections 1312 and 1313respectively. As described above, display unit 113 can include wirelessradio transceivers (e.g., 1162 of FIG. 11) which are configured forcommunication outside of ad-hoc wireless personal area network 1100. Asan example, implementations of the IEEE 802.11 standards can be used toimplement communications between ad-hoc wireless personal area networks1100, local area wireless repeater 1302, cellular/wireless repeater1303, and local reference station 1304. In one embodiment, local areanetwork 1301 utilizes a network protocol that implements an IP addressbased communication scheme to implement communications between variouselements. In FIG. 13, local area wireless repeater 1302, cellularwireless repeater 1303, and local reference station 1304 are shown asseparate components which represent a fixed infrastructure forimplementing local area network 1301. However, in accordance withembodiments some of the functions separately shown in local area network1301 can be combined in a single device. In one embodiment, a displayunit 113 that includes one or more of the different types of ad-hocwireless personal area networks 1100 can be configured to store andforward messages to/from other of the ad-hoc wireless personal areanetworks 1100 comprising local area network 1301. Alternatively, localarea wireless repeater 1302 may be mounted in another vehicle at a siteat which local area network 1301 is located.

In one embodiment, communication between Internet 1310 and local areanetwork 1301 is accomplished via cellular/wireless repeater 1303. In oneembodiment, cellular/wireless repeater 1303 comprises a cellulartelephone transceiver for communicating with Internet 1310 via cellularnetwork 1350 using wireless connection 1351. Cellular/wireless repeater1303 further comprises a wireless transceiver for communication withother components of local area network 1301. An example of acommercially available model of cellular/wireless repeater 1303 is theNomad® handheld computer from Trimble Navigation of Sunnyvale, Calif. Inone embodiment, communication between Internet 1310 and local areanetwork 1301 is accomplished via wireless transceiver 1305 which iscommunicatively coupled with Internet 1310. Wireless transceiver 1305 isin turn communicatively coupled with local area wireless repeater 1302using wireless connection 1331. It is noted that in accordance with oneembodiment, a connection to Internet 1310 may be available at the siteat which local area network 1301 is located and that wirelesstransceiver 1305 may fulfill the function of local area wirelessrepeater 1302 in that instance. In accordance with another embodiment, aconnection to Internet 1310 can be made directly from display unit 113.In operation, display unit 113 can initiate wireless communication withInternet 1310 either directly using wireless radio transceiver 1162, orvia local area wireless repeater 1302 and/or cellular/wireless repeater1303. In one embodiment, establishing communications with Internet 1310is accomplished in a manner that is transparent to a user of displayunit 113. In other words, display unit 113 can be configured toautomatically exchange messages with local area wireless repeater 1302,cellular/wireless repeater 1303, or a website of Internet 1310 withoutthe necessity of user initiation or intervention. These messages can beused for receiving updates, position reporting of load 104, or liftingdevice 120. The data in these messages can be used for purposesincluding, but not limited to, collision monitoring, traffic control ata site, hazard avoidance, site monitoring, status and positionmonitoring of equipment, vehicle logging, etc.

In accordance with embodiments, Internet 1310 is coupled with ageographically independent corrections system 1315 and with ageographically dependent correction system 1320. In accordance withvarious embodiments, it is desired to deliver reference data to GNSSreceivers to improve the precision of determining a position. Thisreference data allows compensating for error sources known to degradethe precision of determining a position such as satellite and receiverclock errors, signal propagation delays, and satellite orbit error. Inone embodiment, geographically independent corrections system 1315determines the correct position of GNSS satellites in space as well asclock errors associated with each of the GNSS satellites and distributesan error message 1316 to facilitate a GNSS receiver to refinedetermining its position with a precision of ten centimeters or less. Inaccordance with various embodiments, error message 1316 can bedistributed via Internet 1310. In one embodiment, error message 1316 issent from Internet 1310 to communication satellites 1340 via uplink1341. Communication satellites 1340 then convey error message 1316 tolocal area network 1301 via wireless connection 1342. In one embodiment,GNSS receiver 1164 of display unit 113 determines which GNSS satellitesare in its field of view and uses the orbit and clock error datapertaining to these satellites from error message 1316 to refinedetermining its position. Alternatively, error message 1316 can beconveyed from communication satellites 1340 to local area wirelessrepeater 1302 or cellular/wireless repeater 1303. In another embodiment,error message 1316 is sent via cellular network 1350 tocellular/wireless repeater 1303 and then distributed throughout localarea network 1301.

Geographically dependent corrections system 1320 uses a network ofreference stations to determine error sources which are more applicableto a particular to the region due to local weather and/or localatmospheric conditions due to ionospheric and/or troposphericpropagation delays. In accordance with one embodiment, a subset of thenetwork of reference stations can be selected in order to generatereference data descriptive of these error sources. This reference datacan be used by GNSS receiver 1164 to refine determining its positionwith a precision of approximately one centimeter or less. Again, thereference data descriptive of these error sources can be distributed viaInternet 1310 to communication satellites 1340, or to cellular network1350 for distribution to local area network via cellular/wirelessrepeater 1303 for example. One implementation of geographicallydependent correction system 1320 is described in U.S. patent applicationSer. No. 12/241,451, titled “Method and System for Location-DependentTime-Specific Correction Data,” by James M. Janky, Ulrich Vollath, andNicholas Talbot, attorney docket number TRMB-2011, assigned to theassignee of the present application and incorporated by reference in itsentirety herein.

FIG. 14 is a flowchart of a method 1400 for communicatively coupling asensor unit system in accordance with one or more embodiments. Inoperation 1410 of FIG. 14, data is received from a first globalnavigation satellite system (GNSS) receiver of a display unit, whereinthe first GNSS receiver is configured for determining a position of thedisplay unit in three dimensions. As described above, in accordance withvarious embodiments display unit 113 comprises GNSS receiver 1164 whichis configured to determine the position of display unit 113 in threedimensions based upon GNSS signals received via GNSS antenna 1165.Furthermore, in accordance with various embodiments display unit 113further comprises one or more wireless radio transceivers 1165. Inaccordance with various embodiments, at least one of the wireless radiotransceivers 1165 is configured for communicating via a wirelesspersonal area network connection (e.g., 111 of FIG. 11).

In operation 1420 of FIG. 14, data is received from a second GNSSreceiver of a sensor unit via a wireless radio transceiver using awireless Personal Area Network (PAN) connection, wherein the second GNSSreceiver is configured for determining a position of the sensor unit inthree dimensions. In accordance with various embodiments display unit113 receives data from hook block sensor assembly 1101 via wirelessconnection 1111. As described above, wireless connection 1111 is awireless personal area network connection in accordance withembodiments. In accordance with various embodiments hook block sensorassembly 1101 can convey data from one or more GNSS receiver 1103 viawireless connection 1111. Additionally, hook block sensor assembly 1101can convey data from one or more of load monitors 214.

Lifting Device Sensor Unit System

In various embodiments of the present technology, a real-time locationsystem positioning system is used to determine the position of amoveable object such as a vehicle, or implement, at a site. While muchof the following discussion will be directed at a sensor unit disposedupon the load line of a lifting device, it is appreciated that variousembodiments may be utilized on other moveable objects and/or vehicleswhich are broadly described as mobile construction devices. Mobileconstruction devices are devices which can move under their own power orare frequently relocated. Thus, a lifting device is just one specificexample of a mobile construction device. For the purpose of the presentapplication, the term “real-time location system (RTLS)” is directed topoint-to-point radio ranging systems comprising a first radio device ata sensor system and one or more second radio devices disposed atknowable locations at a site. A radio propagation path exists betweenthe first radio device at the sensor unit and each of the second radiodevices not at the sensor unit. For each pair of first radio device andsecond radio device, at least one device must act as a radio transmitterto provide a radio signal. An estimate of range between the first radiodevice and each second radio device can be made by transmitting a radiosignal along this propagation path and measuring a physical propertywell correlated to range. Examples of well correlated physicalproperties include signal strength, time of flight (or the related timedifference of arrival), and signal phase. Another example of a wellcorrelated physical property, which can be considered a form of signalstrength measurement, is presence. In other words, a radio device isdetected and considered present if it is within a certain range, and notdetected outside of that range.

If an initial position of the sensor unit is known, via point-to-pointradio ranging or another means, changes in position can be estimated bymeasuring physical properties well correlated to changes in range suchas carrier or modulation frequency offsets.

In some instances, the range estimate can be improved by also providinginformation regarding the propagation path, such as the location ofobjects known to reflect radio signals. This additional information maythen be used to mitigate distortion errors in the measurement to rangeestimation function.

In one or more embodiments, the radio transmitter may, in fact, becomprised of multiple sub-devices, such as multiple antennas, atslightly different physical locations. Combining the estimates of rangefrom each sub-device may provide an estimate of the direction angle fromwhich the radio signal arrives. A common estimate to use in estimatingangle of arrival is phase. In another embodiment, the relative signalstrength at each of a plurality of antennas can be measured and used todetermine the direction back to the device which generated the radiosignal such as RTLS tags. Alternatively, one or more directionalantennas can be used to determine the direction from the sensor unit tothe device transmitting the radio signal. However, it is understood thatany physical property well correlated to range or change in range wouldbe suitable to this use. In some instances, the angle informationprovides better accuracy than the range information by removing rangeerrors that are common to each sub-device. For example, when measuringtime of flight there may not be a reliable estimate of the transmissiontime resulting in large range errors to each sub-device, but having anaccurate measurement of the receive time at each sub-device would allowthe calculation of the angle from which the transmission must havearrived.

FIG. 15A is a diagram of an example lifting device sensor unit 1500A inaccordance with one or more embodiments. For the sake of brevity,components of lifting device sensor unit 1500A which were previouslydescribed with reference to FIG. 2A will not be repeated in thefollowing discussion. In FIG. 15A, lifting device sensor unit 1500Acomprises a positioning transceiver 1501, a communications linkcontroller 1502, and a second communications link controller 1503, and aposition determining component 1505. In accordance with variousembodiments, communications link controllers 1502 and/or 1503 may bewireless communications link controllers, wired communications linkcontrollers, or a combination thereof. In accordance with variousembodiments, communications link controllers 1502 and/or 1503 can be oneor more a transmitter, a receiver, or a transceiver. It is noted thatthat while GNSS receivers 213A and 213B are depicted, in someembodiments these are not utilized and thus are not required to beincluded in all embodiments of lifting device sensor unit 1500A. It isnoted that while the following discussion describes embodiments directedto locating lifting device sensor unit 1500A on the load line of alifting device, various embodiments are well suited for use on othermoveable objects or vehicles as well.

In accordance with one or more embodiments, positioning transceiver 1501comprises a RTLS transceiver and generates a signal to positioning tags(e.g., RTLS tags) which are located at knowable locations at a site(e.g., a job site, construction site, or the like). Based upon signalsreceived in response from the RTLS tags, disposed within an operatingenvironment of lifting device sensor unit 1500A, position determiningcomponent 1505 (depicted in greater detail in FIG. 17 and alsogenerically shown in FIGS. 20 and 21) can determine the position oflifting device sensor unit 1500A in at least two dimensions. Inaccordance with one or more embodiments, position determining component1505 can determine a distance to each of the RTLS tags based upon thesignal strength of the response each RTLS tag sends to positioningtransceiver 1501. In other embodiments, position determining component1505 can determine a distance to each of the RTLS tags based uponmeasurements of the respective time of flight of a signal frompositioning transceiver 1501 to a given RTLS tag and the reply from theRTLS tag. In other words, the time elapsed from when positioningtransceiver 1501 generates a signal to a given RTLS tag to whenpositioning transceiver 1501 receives a reply from that given tag isused by position determining component 1505 to determine a distance toeach of the RTLS tags. In another embodiment, the phase of an incomingsignal to positioning transceiver 1501 can be determined using oneantenna or two or more antennas. When using two or more antennas, thisfacilitates determining the range from the RTLS tag to lifting devicesensor unit 1500A based upon the angle of arrival at the variousantennas. Various embodiments may utilize either the signal strengthtechnique, the time of flight technique, or the phase differencetechnique exclusively, while other embodiments may utilize a combinationof the techniques described above.

Referring now to FIG. 15B, a sensor unit 1500B is shown. In accordancewith one or more embodiments, sensor unit 1500B comprises a sensor unithaving a different form factor than previously discussed with referenceto lifting device sensor unit 1500A or sensor unit 110 of FIGS. 2A, 2B,2C, and 2D. It is noted that in the embodiment of FIG. 15B, sensor unit1500B is not configured to be coupled with the load line of a liftingdevice. With reference to FIG. 15C, sensor unit 1500B can be used with avariety of mobile construction devices 1590 in various embodimentsincluding, but not limited to: loaders, trucks, dump-trucks, mixers,scrapers, bulldozers, backhoes, fork lifts, excavators, tractors,pavers, rollers, lifting devices, etc. It is noted that load monitors214A and 214B can be aligned to direct field of view 218A and 218B in adifferent orientation than that shown in FIG. 15B. For example, whenmounted on a mobile construction device 1590 such as a truck orbulldozer, it may be desirable to have field of view 218A and 218Bdirected in a substantially horizontal orientation. In accordance withone or more embodiments, the orientation of load monitors 214A and 214Bcan be adjusted by altering the angle by which sensor unit 1500B iscoupled with a particular mobile construction device 1590, or may bedisposed at a different position of sensor unit 1500B. As shown in FIG.15C, sensor unit 1500B is disposed such that field of view 218A isaligned in a substantially horizontal orientation. In FIG. 15C, sensorunit 1500B is communicatively coupled with display unit 113 and with aGNSS antenna unit 1820. In accordance with one or more embodiments, thecommunicative coupling of sensor unit 1500B, display unit 113, and GNSSantenna unit 1820 is accomplished using wireless communication links.

In FIG. 15B, sensor unit 1500B comprises a positioning transceiver 1501,a communications link controller 1502, and a second communications linkcontroller 1503, and a position determining component 1505. Inaccordance with various embodiments, communications link controllers1502 and/or 1503 may be wireless communications link controllers, wiredcommunications link controllers, or a combination thereof. It is notedthat that while GNSS receivers 213A and 213B are depicted, in someembodiments these are not utilized and thus are not required to beincluded in all embodiments of sensor unit 1500B.

Housing 1580 may be configured to removably couple around the componentsof sensor unit 1500B. Housing 1580 is typically comprised of a rigid orsemi-rigid material or materials. In one embodiment, all or a portion ofhousing 1580 is made of an injection molded material such as high impactstrength polycarbonate. In one embodiment at least a portion of housing1580 is transparent to GNSS satellite signals such that these signalscan be received by GNSS receiver(s) 213A, 213B, which are coupled withhousing 1580 and secured inside housing 1580. In some embodimentshousing 1580 comprises a plurality of sections (not shown) that join,fasten, latch, or otherwise couple with one another to form housing 1580and to removably couple with a mobile construction device.

With continued reference to FIG. 15B, the removably couplablecharacteristic of housing 1580 facilitates field mounting and removal ofsensor unit 1500B. In this manner, a construction company or cranerental company, for example, can flexibly utilize sensor unit 1500B witha plurality of different mobile construction devices by moving sensorunit 1500B from one mobile construction device to another mobileconstruction device. The removably couplable characteristic of housing1580 also facilitates the use of sensor unit 1500B on mobileconstruction devices from a variety of manufacturers as no permanentmounting, hardwiring to the electrical system of the mobile constructiondevice, or interfacing with the operating system of the mobileconstruction device is required.

In accordance with one or more embodiments, positioning transceiver 1501comprises a RTLS transceiver and generates a signal to positioning tags(e.g., RTLS tags) which are located at knowable locations at a site(e.g., a job site, construction site, or the like). Based upon signalsreceived in response from the RTLS tags, disposed within an operatingenvironment of sensor unit 1500B, position determining component 1505(depicted in greater detail in FIG. 17 and also generically shown inFIGS. 20 and 21) can determine the position of sensor unit 1500B in atleast two dimensions. In accordance with one or more embodiments,position determining component 1505 can determine a distance to each ofthe RTLS tags based upon the signal strength of the response each RTLStag sends to positioning transceiver 1501. In other embodiments,position determining component 1505 can determine a distance to each ofthe RTLS tags based upon measurements of the respective time of flightof a signal from positioning transceiver 1501 to a given RTLS tag andthe reply from the RTLS tag. In other words, the time elapsed from whenpositioning transceiver 1501 generates a signal to a given RTLS tag towhen positioning transceiver 1501 receives a reply from that given tagis used by position determining component 1505 to determine a distanceto each of the RTLS tags. In another embodiment, the phase of anincoming signal to positioning transceiver 1501 can be determined usingtwo or more antennas. This facilitates determining the range from theRTLS tag to lifting device sensor unit 1500B based upon the angle ofarrival at the various antennas. Various embodiments may utilize any ofthe signal strength technique, the time of flight technique, or thephase difference technique exclusively, while other embodiments mayutilize a combination of the techniques described above. For thepurposes of the following discussions, the term “sensor unit” isunderstood to refer to either of, or both, lifting device sensor unit1500A of FIG. 15A and sensor unit 1500B of FIG. 15B.

RTLS-Based Position Determination

Referring to FIG. 16, in one embodiment, lifting device 120 or othermobile construction device 1590 is located at a site (job site,construction site, or the like) where tags 1601, 1602, and 1603 havebeen placed at knowable locations. A sensor unit 1500 is coupled withthe lifting device or other mobile construction device 1580. Inaccordance with one or more embodiments, a positioning transceiver 1501generates a signal to one or more of the tags which are place atknowable locations about or near the site. It is noted that one or moreembodiments can implement a network of WiFi wireless routers in theplace of RTLS tags, radio-frequency identification (RFID) tags, or othercommunication devices for which determination of position can be made.As an example, tags 1601, 1602, and 1603 may be cellular telephones, orsimilar devices, which have the capability to determine their ownposition (e.g., via cellular triangulation, or an embeddedsatellite-based positioning capability). Additionally, some cellulartelephones are configured to determine their position via acommunication connection to a local WiFi hotspot.

Positioning transceiver 1501 can utilize a variety of signal frequenciesincluding, but not limited to: the 2.4 GHz band used under the 802.11standard, 303 MHz, 315 MHz, 418 MHz, 433 MHz, 868 MHz, and 915 MHz. Thesignal from positioning transceiver 1501 can be of various forms.Additionally, positioning transceiver 1501 can generate a continuoustransmission modulated in frequency, phase, amplitude, or a combinationof these. Such modulations are commonly referred to as amplitudemodulation (AM), frequency modulation (FM), on-off keying (OOK),continuous phase modulation (CPM), multiple frequency shift keying(MFSK), binary phase shift keying (BPSK), quadrature phase shift keying(QPSK), frequency shift keying (FSK), quadrature amplitude modulation(QAM), phase shift keying (PSK), orthogonal frequency divisionmultiplexing (OFDM), and chirping. Another radio signal used inaccordance with various embodiments is short pulses, commonly referredto as ultra-wide band (UWB).

In FIG. 16, tags 1601, 1602, and 1603 can be placed on buildings, orother structures on or around the site, which are fixed, or not likelyto be moved within a designated time period. When emplaced, the positionof each of tags 1601, 1602, and 1603 can be recorded using, for example,a GNSS receiver or with reference to a local coordinate system. Inaccordance with one or more embodiments, the positions andidentification data of tags 1601, 1602, and 1603 can be stored in aposition database or location server such as local reference station1304 of FIG. 13, or stored locally such as in a memory or database ofposition determining component 1505 (such as tag position database 1715of FIG. 17), or within a memory of the tag itself. Alternatively, iftags 1601, 1602, and 1603 are capable of determining their own positionin real-time, tags 1601, 1602, and 1603 could determine their positionin response to a query from positioning transceiver 1501 and send thatposition in response. Thus, for the purpose of the present discussion,the term “knowable location” means that the location of tags 1601, 1602,and 1603 can either be previously determined, or determined inreal-time, and accessed by lifting devices sensor unit 1500. In one ormore embodiments, tags 1601, 1602, and 1603 generate signals at regularintervals comprising a unique identifier and other status information.Alternatively, tags 1601, 1602, and 1603 may generate a reply inresponse to a message generated by positioning transceiver 1501. Usingthis unique identifier, position determining component 1505 canidentify, and determine the knowable location, of each of tags 1601,1602, and 1603 and determines the distance from lifting device sensorunit 1500 to each of the tags from which it has received a response.Position determining component 1505 can then determine the position oflifting device sensor unit 1500 by trilateration. Because RTLS messagescan include more data, other information such as a timestamp of when themessage was generated by the respective tag, or its position in thelocal/global coordinate system, may be included.

In one or more embodiments, tags 1601, 1602, and 1603 are RFID tags. Inone embodiment, positioning transceiver 1501 generates an interrogationcommand which activates or “wakes up” any of tags 1601, 1602, and 1603which are in range of the signal from positioning transceiver 1501. Tags1601, 1602, and 1603 can be passive tags which use the interrogationsignal power to activate and operate a circuit that accesses storedinformation. Typically, once activated, RFID tags modulate a reflectioncoefficient of the tag antenna with a suitable data information signalread out from tag memory. The antenna reflects the incident signal fromthe interrogator back to the interrogator with the tag data modulatedonto the reflected signal. In one or more embodiments, tags 1601, 1602,and 1603 send a reply to positioning transceiver 1501 comprising aunique identifier. Using this unique identifier, position determiningcomponent 1505 can identify, and determine the knowable location, ofeach of tags 1601, 1602, and 1603 and determines the distance fromlifting device sensor unit 1500 to each of the RFID tags from which ithas received a response. Alternatively, tags 1601, 1602, and 1603 can beactive tags which have a source of power available when generating areply to the interrogation signal. Position determining component 1505can then determine the position of lifting device sensor unit 1500 by,for example, trilateration. Furthermore, in one or more embodiments,position determining component 1505 can derive a rough estimate of itsposition based upon which tags respond, or do not respond, to a querycommand from positioning transceiver 1501.

In accordance with one or more embodiments, position determiningcomponent 1505 determines the distance to a given tag based upon thesignal strength of the received reply from that tag. For example, someRTLS reader/interrogators provide an interface for capturing the signalstrength of received signals. This permits sending signal strength datato position determining component 1505 via a signal strength input 1705(e.g., signal strength input 1705 of FIG. 17). Position determiningcomponent 1505 can then, for example, calculate a signal strengthdirectly from a signal or alternatively can access a look-up table(e.g., signal strength look-up table 1720 of FIG. 17) which correlates agiven signal strength with a range to the responding tag. It is notedthat signal strength is subject to various effects such as antennaorientation and multi-path delay. In one embodiment, a model of receivedsignal strength from various tags can be created in advance of theoperation of lifting device sensor unit 1500 to improve the precision ofposition location. This model can account for some of these effectswhich might otherwise impair the precision of determining the positionof lifting device sensor unit 1500. Additionally, this model can becreated, or modified, based upon signals received by lifting devicesensor unit 1500 and can account for the location of objects at a sitewhich are known to reflect radio signals. This additional informationmay be used to mitigate distortion errors in the measurement to rangeestimation function. In various embodiments, this model can be storedupon lifting device sensor unit 1500 and accessed by positiondetermining component 1505 to facilitate determining the distance tovarious tags. Alternatively, this model can be stored at anotherlocation, such as local reference station 1304 and accessed via awireless communication network such as local area network 1301 of FIG.13. It is noted that determination of the position of lifting devicesensor unit 1500 can also be performed by local reference station 1304which can receive raw data, or post-processed signal data, from liftingdevice sensor unit 1500 and perform the operations necessary fordetermining its location such as determining the distance from liftingdevice sensor unit 1500 to the various tags.

In other embodiments, position determining component 1505 determines around-trip time of flight of signals to and from positioning transceiver1501. In other words, positioning transceiver 1501 sends a respectivesignal to each of tags 1601, 1602, and 1603 and receives a respectivereply. For example, positioning transceiver 1501 can generatetimestamps, which are sent to a timestamp receiver of positiondetermining component 1505 (e.g., time stamp receiver 1710 of FIG. 17).Using this data, position determining component 1505 can analyze thistime differential to determine the distance from lifting device sensorunit 1500 to each of the respective tags 1601, 1602, and 1603. Positiondetermining component 1505 can account for the time it takes each tagsto process the interrogation message and generate a reply in order tomore accurately determine the time it took for a message to reach eachrespective tag and the time it took for the reply from that tag toarrive at positioning transceiver 1501. This time can then be multipliedby the speed to light and divided by two to determine the distance fromlifting device sensor unit 1500 and each respective tag. One advantageof using a round-trip time of flight calculation is that there is nonecessity for synchronizing clocks between positioning transceiver 1501and the tags with which it communicates. It is noted that there are avariety of methods for determining the distance between objects usingRTLS components which may also be used in accordance with variousembodiments. However, in one or more embodiments, clock synchronizationbetween positioning transceiver 1501 and tags 1601, 1602, and 1603 canbe implemented. This may facilitate other methods of determining thedistance between positioning transceiver 1501 and tags 1601, 1602, and1603 such as time-of-flight, time of arrival, time difference ofarrival, etc.

In another embodiment, phase measurements of the signals received fromtags 1601, 1602, and 1603 can be performed to determine the position oflifting device sensor unit 1500. As will be discussed in greater detailbelow, in one or more embodiments phase measurement comprises measuringthe number of integer wavelengths and partial wavelengths frompositioning transceiver 1501 and each tag responding to positioningtransceiver 1501 as is often performed with respect to GNSS signal phasemeasurements made by a GNSS receiver.

In accordance with various embodiments, having determined the distancefrom lifting device sensor unit 1500 to each of the tags, positiondetermining component 1505 determines the position of lifting devicesensor unit 1500 by trilateration. In other words, having determined arespective distance to each of tags 1601, 1602, and 1603 (e.g., distance1601, 1602, and 1603 of FIG. 16), position determining component 1505derives spheres/hyperboloids which are centered at the location of tags1601, 1602, and 1603 and have a radius corresponding to the respectivedistance to each of tags 1601, 1602, and 1603. The location of liftingdevice sensor unit 1500 is determined to be the location at which allthree spheres/hyperboloids overlap. It is noted that while the presentdescription discusses generating spheres/hyperboloids, that only partialspheres/hyperboloids are depicted in FIG. 16 for the purpose of clarity.Further, while only three tags are illustrated in FIG. 16 and describedin conjunction with the presented examples, it is appreciated that manymore may be emplaced and utilized.

FIG. 17 is block diagram showing components of an example positiondetermining component 1505, in accordance with an embodiment. In someembodiments, position determining component 1505 comprises signalstrength input 1705 (which is configured to receive output frompositioning transceiver 1501). For example, signal strengths can becalculated directly from a received signal or can be analyzed usingsignal strength look-up table 1720. It is noted that processor 1725 canalso access a mapping of signal strengths for the site at which liftingdevice sensor unit 1500 is located to facilitate locating the positionof lifting device sensor unit 1500. This mapping can be stored, forexample in memory 1730. In one or more embodiments, position determiningcomponent 1505 also comprises a timestamp receiver 1710 configured toreceive a timestamp from positioning transceiver 1501 when a signal isgenerated or received. This facilitates determining a round trip time offlight for signals between lifting device sensor unit 1500 and, forexample, tags 1601, 1602, and 1603.

In one or more embodiments, position determining component 1505 furthercomprises a tag position database 1715. Tag position database 1715 canbe a searchable database, or look-up table, which correlates a uniqueidentifier of each respective tag with its knowable position. It isnoted that components of position determining component 1505 can beupdated from, for example, local reference station 1304 or anothersource, via wireless communications link controllers 1502 and 1503.Alternatively, the knowable location of one or more of tags 1601, 1602,and/or 1603 can be stored, for example, at a location apart from sensorunit 1500 such as at local reference station 1304. Processor 1725 is forimplementing computer-readable and computer-executable instructions. Thecomputer-readable and computer-executable instructions reside, forexample, in tangible data storage features such as memory 1730 and/ornon-volatile memory 1735. More specifically, instructions for executinga method for providing lifting device sensor unit location data can bestored in memory 1730, or non-volatile memory 1735. In one or moreembodiments, position determining component 1505 further comprises adata output 1740 for outputting position data to, for example,communications link controllers 1502 and/or 1503.

In FIG. 17, phase measurement component 1740 performs analysis of thesignals received from tags 1601, 1602, and 1603 to determine theposition of lifting device sensor unit 1500. Typically, phasemeasurements are made within one radio frequency cycle of 360 degrees.Therefore, an estimate of the number of integer wavelengths betweentransceiver 1501 and each tag responding to it is made by phasemeasurement component 1740. In one embodiment, data from multiple tagsis taken into account to reduce the search space needed to find anacceptable estimate of all integer wavelengths from all tags respondingto positioning transceiver 1501. One system which performs this type ofphase measurement is described in U.S. Pat. No. 5,519,620 titledCentimeter Accurate Global Positioning System Receiver for On-The-FlyReal-Time Kinematic Measurement and Control by Nicolas C. Talbot et al.U.S. Pat. No. 5,519,620 is assigned to the assignee of the presentapplication and is incorporated in its entirety herein. In at least oneembodiment, signal strength of signals received from responding tags(e.g., 1601, 1602, and 1603) can be used to provide an initial distanceestimate from each of tags 1601, 1602, and 1603 to positioningtransceiver 1501. This facilitates determining the number of integerwavelengths and partial wavelengths between positioning transceiver 1501and one or more of tags 1601, 1602, and 1603. Similarly, round-trip timeof flight of signals to and from positioning transceiver 1501 can beused to provide an initial estimate from each of tags 1601, 1602, and1603 and positioning transceiver 1501 and thus facilitate determiningthe number of integer wavelengths and partial wavelengths betweenpositioning transceiver 1501 and one or more of tags 1601, 1602, and1603.

Example Communication Network

FIG. 18 is a block diagram of an example communication network 1800 inaccordance with one or more embodiments. In FIG. 18, a sensor unit 1500(e.g., lifting device sensor unit 1500A of FIG. 15A, or sensor unit1500B of FIG. 15B) is communicatively coupled with display unit 113 viacommunication connection 1811. For the purpose of brevity, acomprehensive illustration of components of sensor unit 110 which areimplemented as sensor unit 1500 are not shown in FIGS. 18 and 19.However, it is understood that various features and components of sensorunit 110 as described above are combined in implementations of sensorunit 1500. In FIG. 18, sensor unit 1500 comprises a positioningtransceiver 1501. In accordance with various embodiments, positioningtransceiver 1501 is a point-to-point radio ranging system such as, whichmay include but is not limited to, an RTLS or RFID transceiver. Sensorunit 1500 further comprises a power supply 1804 for supplying power tosensor unit 1500. It is noted that power supply 1804 can comprisebatteries and/or a connection to vehicle supplied power.

Communications link controllers 1502, 1503, and 1862 providecommunications with other components of local area network 1301 andcommunication network 1800. It is noted the communications linkcontrollers 1502, 1503, and 1862 can be one or more of a transmitter, areceiver, or a transceiver in accordance with various embodiments. As anexample, in one embodiment communications link controller 1502 and/or1862 may be configured to operate on any suitable wireless communicationprotocol including, but not limited to: WiFi, WiMAX, implementations ofthe IEEE 802.11 specification, cellular, two-way radio, satellite-basedcellular (e.g., via the Inmarsat or Iridium communication networks),mesh networking, implementations of the IEEE 802.15.4 specification forpersonal area networks, and a short range wireless connection operatingin the Instrument Scientific and Medical (ISM) band of the radiofrequency spectrum in the 2400-2484 MHz range (e.g., implementations ofthe Bluetooth® standard). Personal area networks refer to short-range,and often low-data-rate, wireless communications networks. Additionally,communications link controller 1503 and/or 1862 may operate onimplementations of any suitable communication protocol including, butnot limited to: RS-232, Ethernet, and TCP/IP protocols. In one or moreembodiments, communications link controllers 1502 and 1503 may both beconfigured to communicate using the wireless communication protocolslisted above. It is understood that communications link controllers1502, 1503, and 1862 may be separate devices, may be dedicated hardwarewithin another device, may be implemented in computer readableinstructions, or may comprise a combination of such techniques.Similarly, physical layer interfaces 1806 and 1863 may be separatedevice, or may dedicated hardware within another device. In accordancewith various embodiments, components of communication network 1800 maybe configured for automatic detection of other components and forautomatically establishing communications. Alternately, components ofcommunication network 1800 may be preconfigured for communicating withother components or can implement manual configuration of components forcommunicating with other components. In one embodiment, sensor unit 1500only uses communications link controllers 1502 and/or 1503 tocommunicate with display unit 113 via communication network 1800. Forcommunication with components outside of communication network 1800communications controller 1862 is used to communicate within local areanetwork 1301, such as with local reference station 1304 of FIG. 13.Thus, sensor unit 1500 can forward positioning data (e.g., raw data,processed data, or position fixes) to display unit 113 via communicationconnection 1811. This data can either be used by display unit 113, orforwarded to another location.

Sensor unit 1500 further comprises one or more load monitors 1807 whichare implemented to accomplish load monitoring and/or as described abovewith reference to load monitors 214. Load monitors 1807 can further beused for lift plan implementation, position control, collisionmonitoring, and initiating avoidance actions as discussed above withreference to sensor unit components 216 of FIG. 2A. These components ofsensor unit 1500 are communicatively and/or electrically coupled withone another as required for performing functions of load monitoring,collision avoidance, and/or load hazard avoidance as described above.

In accordance with various embodiments, the components of sensor unit1500 are housed within a housing 201 (see e.g., FIG. 2D). In oneembodiment, housing 201 is coupled with hook 111 (see e.g., FIG. 2D) andone or more of the components of sensor unit 1500 that described abovein FIGS. 2A, 2B, and 3 are coupled with housing 201. Alternatively, thecomponents of sensor unit 1500 may be coupled with hook 111 and enclosedby housing 201. It is further noted that other components of sensor unit110 (e.g., sound emitting device 251, light emitting device 252, accesshatch 253, recharge contacts 254, and/or protective bumper 255) may beincluded in housing 201 in accordance with various embodiments.

As discussed above, display unit 113 may be a dedicated display with atransceiver or may be part of an electronic device such as smart phone,netbook, notebook computer, tablet computer, or the like. In theembodiment of FIG. 18, display unit 113 is removeably coupled with adocking station 1808 which provides connection to a power source (notshown) and a communication connection with L1 GNSS antenna 1810. Inaccordance with various embodiments, display device 1860 may be a liquidcrystal device, cathode ray tube, or a touch screen assembly configuredto detect the touch or proximity of a user's finger, or other inputdevice, at or near the surface of display device 1860 and to communicatesuch an event to a processor (e.g., processors 1006A, 1006B, and/or1006C of FIG. 10). Display unit 113 further comprises batteries 1861 forproviding power to display unit 113 when it is de-coupled from dockingstation 1808.

Display unit 113 further comprises one or more communicationscontrollers 1862 and physical layer interface 1863 for communicatingwith other components of communication network 1800. In the embodimentof FIG. 18, display unit 113 comprises a GNSS receiver 1864 and GNSSantenna 1865 configured for receiving satellite navigation signals andfor determining the position of display unit 113. As shown in FIG. 18,display unit 113 is communicatively coupled with L1 GNSS antenna 1810which is used to receive satellite navigation signals when display unit113 is coupled with docking station 1808. This may improve the receptionof satellite navigation signals which may be blocked or degraded whendisplay unit 113 is located within cab 121. An example of a commerciallyavailable model of display unit 113 is the Yuma® computer from TrimbleNavigation of Sunnyvale, Calif.

As described above, communications controllers 1862 may operate on anysuitable communication protocol including, but not limited to: RS-232,Ethernet, and TCP/IP, WiFi, WiMAX, implementations of the IEEE 802.11specification, cellular, two-way radio, satellite-based cellular (e.g.,via the Inmarsat or Iridium communication networks), mesh networking,implementations of the IEEE 802.15.4 specification for personal areanetworks, and a short range wireless connection operating in theInstrument Scientific and Medical (ISM) band of the radio frequencyspectrum in the 2400-2484 MHz range (e.g., implementations of theBluetooth® standard). In accordance with embodiments of the presenttechnology, components of communication network 1800 are configured forautomatic detection of other components and for automaticallyestablishing wireless communications. In one embodiment, display unit113 comprises a first wireless radio transceiver 1862 for communicatingwith other components of communication network 1800 (e.g., with awireless communications link controller 1502) and one or more wirelessradio transceivers 1862 for wirelessly communicating outside ofcommunication network 1800.

FIG. 19 is a block diagram of an example communication network 1900 inaccordance with one or more embodiments. In FIG. 19, communicationnetwork 1900 comprises sensor unit 1500 and display unit 113 asdescribed above with reference to FIG. 18. In FIG. 19, communicationnetwork 1900 further comprises GNSS antenna unit 1820. In the embodimentof FIG. 19, positioning transceiver 1501 and position determiningcomponent 1505 are configured for determining the position of sensorunit 1500. In the embodiment of FIG. 19, sensor unit 1500 communicateswith display unit 113 via communications connection 1911 and displayunit 113 communicates with GNSS antenna unit 1820 via communicationsconnection 1912.

Communications link controllers 1502 and 1503 can provide communicationswith other components of local area network 1301 and communicationnetwork 1900 of FIG. 19. As an example, in one embodiment communicationslink controller 1502 may be configured to operate on any suitablewireless communication protocol including, but not limited to: WiFi,WiMAX, implementations of the IEEE 802.11 specification, cellular,two-way radio, satellite-based cellular (e.g., via the Inmarsat orIridium communication networks), mesh networking, implementations of theIEEE 802.15.4 specification for personal area networks, and a shortrange wireless connection operating in the Instrument Scientific andMedical (ISM) band of the radio frequency spectrum in the 2400-2484 MHzrange (e.g., implementations of the Bluetooth® standard). Additionally,communications link controller 1503 may operate on any suitablecommunication protocol including, but not limited to: RS-232, Ethernet,and TCP/IP protocols. In one or more embodiments, communications linkcontrollers 1502 and 1503 may both be configured to communicate usingthe wireless communication protocols listed above. In one embodiment,sensor unit only utilizes communications link controller 1502 tocommunicate with display unit 113 via communication network 1900. Forcommunication with components outside of communication network 1900,display unit 113 uses one of communication controllers 1862 tocommunicate within local area network 1301, such as with local referencestation 1304 of FIG. 13. Thus, sensor unit 1500 can forward positioningdata (e.g., raw data, processed data, or position fixes) to display unit113 via communication network 1900. This data can either be used bydisplay unit 113, or forwarded to another location. An example of acommercially available model of GNSS antenna unit is the SPS 882 SmartGPS Antenna from Trimble Navigation of Sunnyvale, Calif. In oneembodiment, GNSS antenna unit 1820 is mounted at the rear of liftingdevice 120 as shown by global navigation satellite receiver 108 of FIG.1A.

In operation, sensor unit 1500, display unit 113, and GNSS antenna unit1820 are configured to implement a communication network to assist in oraccomplish one or more of efficient load delivery, load monitoring,collision avoidance, and load hazard avoidance as described above. Inone embodiment, sensor unit 1500 display unit 113, and GNSS antenna unit1820 are configured to initiate an automatic discovery process in whichcomponents of communication network 1900 detect each other by exchangingmessages without the necessity of user initiation and/or intervention.Additionally, in one embodiment sensor unit 1500, display unit 113, andGNSS antenna unit 1820 are configured to automatically initiateprocesses to assist in or accomplish one or more of efficient loaddelivery, load monitoring, collision avoidance, and load hazardavoidance such as determining the position of sensor unit 1500, displayunit 113, and/or load 104 in manners previously described herein.Furthermore, in one embodiment display unit 113 is configured to sendand receive data outside of communication network 1900. Thus, displayunit can be used to receive updates, correction data for positiondetermination, and other instructions for implementing a plan at a site.Additionally, display unit 113 can be used for storing, forwarding, andreporting data used in site monitoring or other purposes. In oneembodiment, communications link controllers 1502 is used to establishcommunications with display unit 113 and/or GNSS antenna unit 1820. Inone embodiment, communications link controller 1502 is used to establisha wireless connection with local area network 1301 to forward data suchas raw data, processed data, status reports, or position reports. Inanother embodiment, such as when positioning transceiver 1501 is a WiFitransceiver, communications link controller 1502 may be redundant, andwireless connections with local area network 1303 can be establishedusing positioning transceiver 1501.

FIG. 20 is a flowchart of a method 2000 for providing sensor unitlocation data in accordance with one or more embodiments. In operation2010 of FIG. 20 a point-to-point radio ranging system is coupled with amobile construction device 1590 which may be a lifting device such aslifting device 120. As discussed above, various embodiments utilizepoint-to-point radio ranging systems to determine the position of sensorunit 1500.

In operation 2020 of FIG. 20, a position determining componentconfigured for determining a position of a sensor unit in at least twodimensions is coupled with the point-to-point radio ranging system. Asdiscussed with reference to FIGS. 15, 18 and 19, position determiningcomponent 1505 is coupled with sensor unit 1500 which further comprisespositioning transceiver 1501.

In operation 2030 of FIG. 20, a transceiver configured to provideinformation, including the sensor unit position, to a receiving unitlocated apart from the sensor unit is communicatively coupled with theposition determining component. As described with reference to FIGS. 18and 19, at least one of communication controllers 1162 comprises atransceiver which is configured to forward data to local area network1301. In one or more embodiments, this information comprises sensor unitposition, raw positioning data, or post-processed positioning data.

FIG. 21 is a flowchart of a method 2100 for providing sensor unitlocation data in accordance with one embodiment. In operation 2110 ofFIG. 21, communications are received between a point-to-pint radioranging system coupled with a sensor unit of a mobile constructiondevice and a plurality of tags respectively located at a plurality ofknowable locations within an operating environment of the mobileconstruction device.

In operation 2120 of FIG. 21, a position determining component coupledwith the point-to-point radio ranging system is used to determine aposition of the sensor unit in at least two dimensions.

In operation 2130 of FIG. 21, information, including the sensor unitposition is provided to a receiving unit located apart from the sensorunit using a communications link controller communicatively coupled withthe position determining component.

Example Environment for Warning of Proximity in a Worksite

FIG. 22 is a diagram of an example environment 2200 for warning ofproximity in a worksite, in accordance with an embodiment. It should beappreciated that environment 2200 represents a worksite, job site, orconstruction site that comprises equipment, vehicles, buildings,partially constructed structures, people, etc. Embodiments ofenvironment 2200 may or may not include base station 2202. Base station2202 comprises a transceiver that can send and receive signals orcommunications with other transceivers such as transceiver 2204,transceiver 2208, and transceiver 2212. Base station 2202 also comprisesmemory and a processor for storing data and performing calculations. Inone embodiment, environment 2200 does not include base station 2202 andtransceiver 2204, transceiver 2208, and transceiver 2212 eachcommunicate with one another to perform the methods, processes andcalculations of the present technology forming an ad hoc network. Eachof transceiver 2204, transceiver 2208, and transceiver 2212 areassociated with, coupled to, or otherwise attached to object 2206,object 2210, and object 2214 respectively. It should be appreciated thatobject 2206, object 2210, and object 2214 may be a person, a wearableobject worn by a person such as a helmet, a belt, a vest, a shoe, abelt, a headset, or article of clothing, or may be a structure, abuilding, a tree, a piece of requirement, a vehicle, a crane, etc. andmay be referred to as worksite objects. Object 2206, object 2210, andobject 2214, as well as their associated transceiver, may be mobile orstationary.

In one embodiment, a set of transceivers, such as transceiver 2204 andtransceiver 2208, measure distances between each other to preventcollisions on a worksite. The transceivers may be wireless devices. Sometransceivers are carried by personnel on site, installed on vehicles, onbuildings (e.g., walls, beams, etc.) and other obstacles to create avirtual safety envelope around those transceivers. When any two of thosevirtual safety envelopes enter in contact, warnings and/or alarms maywarn the personnel of potential hazards. Applications for thistechnology include, without limitation, indoor worksites, outdoorconstruction sites, or agriculture fields, mining sites, and the like.

In the context of the present disclosure, expressions such as“preventing collisions” should not be taken in the absolute sense sinceperfect safety cannot be expected. Absolute collision prevention is anunattainable goal. The intent of the present technology is therefore toreduce the incidence of accidental collisions.

FIG. 22 may also be described as a schematic representation of an ad-hocnetwork formed by fixed and mobile structures and by personnel on a worksite. Transceivers may be mounted on tower cranes, on mobile cranes,vehicles and, generally, on any fixed or mobile structures. Othertransceivers may be carried by personnel present on site. An ad-hocnetwork is formed between any two or more transceivers.

FIG. 23 is a perspective view of transceiver 2204 which is a batteryoperated transceiver according to a first embodiment and is a wirelesslyrechargeable variant. In one embodiment, transceiver 2302 comprisesantenna 2304, alarm 2308, memory 2310, processor 2312, and display 2314.Transceiver 2302 with its depicted components or accessories may bedescribed as a proximity warning device. Antenna 2304 is for wirelesslycommunicating with other transceivers and base stations and may employ awide range of frequencies and wireless technique including wideband and900 Mhz transmissions. Alarm 2308 is a hardware device that is forissuing or raising an alarm when two safety envelopes contact oneanother and may be referred to as an alarm component. The alarm may be aspeaker to raise an audible alarm, a light for visual display, such asan LED light, or a combination thereof. The light may turn on, flash,blink, change colors, or change in intensity. The speaker may issue anaudible sound or voice. In one embodiment, alarm 2308 is a display, suchas display 2314 that is used to visually represent the safety envelopeand the proximity of two objects. For example, display 2314 may displaya simulation of the worksite and the objects therein. The alarm maycontinue to alarm until the two safety envelopes are no longer incontact. During prolonged contact, the alarm may increase in intensitysuch as growing louder or brighter. The intensity of alarm 2308 may alsoincrease as the safety envelopes grow closer in contact with oneanother. Memory 2310 is for storing data such as data related to thesize or dimension of the safety envelope surrounding transceiver 2302.Memory 2310 may store a predetermined distance defining a first safetyenvelope about a transceiver. Processor 2312 is for determining orcalculating the distance, in three dimensions, between transceiver 2302and another transceiver 2302 that is in proximity to anothertransceiver. Processor 2312 may also determine that an alarm needs to beissued.

FIG. 24 is a perspective view of a transceiver 2402 according to asecond variant and is powered via a wire 2406. Transceiver 2402 alsocomprises antenna 2404 and may comprise the same features and componentsof transceiver 2302 of FIG. 23. Without limitation, transceivers may bebattery operated, may be magnet mountable, and have the approximate sizeof an hockey puck. The transceivers can be fully sealed and may berecharged wirelessly, as in the case of FIG. 23. A version shown on FIG.24 includes a cable or wire 2406 to continuously power the transceiver,without the need to recharge it.

With reference to FIG. 25, a block diagram of person 2500 in a worksite.Person 2500 may also be referred to as personnel or person associatedwith a worksite. Various accessories or articles of clothing of person2500 may be employed for mounting a clipping a proximity warning deviceto. In one embodiment, helmet 2502 is a helmet that has a proximitywarning device mounted to it or built into it. In one embodiment, belt2506 is a belt that has a proximity warning device mounted to it orbuilt into it. In one embodiment, vest 2504 is a vest that has aproximity warning device mounted to it or built into it. The proximitywarning device may be built into, mount to, or clip to the shoulder of avest, jacket or other article of clothing. Helmet 2502 is an exampleapplication in which the battery operated transceiver of FIG. 23 or 24is mounted on a helmet. On the hard hat version, the antenna can belocated in the strap holding the transceiver, to gain 360 degreescoverage. Vibration, audible and visual warning may be available. Alight emitting diode (LED) could be placed just below the front cap toprovide a visual warning. It could show a green-yellow-red status,respectively representing the safe, proximity warning and alarmconditions. In one embodiment, headset 2508 is a headset designed forwearing in or over one or both ears of person 2500 and has a built-inproximity warning device. It should be appreciated that headset 2508 maybe worn over or under helmet 2502 or without helmet 2502. In oneembodiment, headset 2508 comprises headphone technology with speakersdesigned to produce audible sounds in the ear of person 2500. Theheadphone technology may operate such that it could produce a warningsound that simulates to person 2500 the direction of incoming proximitydanger. In one embodiment, headset 2508 comprises a microphone for usewith worksite radio in addition to the proximity warning system.

Active long range radio-frequency identification (RFID) function: eachtransceiver modules may have a unique ID number, allowing RFID type ofunique identification. This version can be smaller, and the battery lifecan be longer because RFID technology only consumes power when in shortrange from a corresponding device. Transmission rate may for example beestimated at once per minute to once per day, depending on the userrequirements.

Each transceiver may have a unique ID number and two-way communicationcapabilities. A software tool may be used to provide a way tocommunicate with a specific transceiver to setup up internal parametersstored in it. Among the settable parameters, the transceiver locationcould be entered when it is installed at a fixed location such as abuilding, the base of a tower crane or other obstacles. The shape andsize of the safety envelope can also be stored in the transceiver. Thisallows the transceivers to be fully autonomous to detect imminentproximity, without depending on satellites, on a local area radionetwork, or on a cellular network.

Generally, transceivers are two-way radio communication devices. Theycontinuously create ad-hoc communication networks between each other,calculating their respective distances, and exchanging their safetyenvelop size. When two envelopes intersect, both transceivers maygenerate warnings and alarms.

Distance versus position: the distance between the transceivers can beused for the safety envelope calculations, leading to possible proximitywarning between them. The position on the other hand may be used indisplay consoles to show the position of the transceivers on screen. Theposition may thus be used as information for machine operators while thedistance measurement may form the safety function. When position cannotbe known with certainty, a display may show warnings and highlight thesafety may be able to show the position of the transceiver and itssafety envelop with more accuracy.

Distance between transceivers may be calculated from one or acombination of the following methods: radio signal strength,triangulation, and TOF (Time of Flight). The transceivers use severalmeans to estimate their position. Some transceivers use radio signalsonly, some combine radio and GNSS (Global Navigation Satellite System),some use radio and a mechanical sensor such as slew sensor, anglesensor, and some use the three, radio, GNSS and mechanical. Transceiversmay be classified in two main categories, the ones with fixed positionsuch as buildings, obstacles or the base of a tower cranes, and the oneson moving vehicle and personnel. Transceivers with fixed position couldhave their position saved in their memory, or could use their GNSS tolocate themselves. The moving transceivers may use the distancecalculation in addition to triangulation with other transceivers havinga known position. GNSS signals could also be used when available toassist fixing their position.

RFID function: the RFID could be executed from long distance compared totraditional RFID. Depending on the antenna, ranges in the order of 1000meters are possible. The range may be user adjustable to provide a meansto optimize battery life. The reader could be a wireless device carriedby a crane rigger or installed on a crane hook to scan what is availablebelow it, or could be a fixed transceiver scanning a work site forinventory purposes.

Display console: proximity warning and alarm indications may beindicated by mean of an audible sounder, visual, vibration or acombination of those. Personnel transceivers may use those three meansin combination. The display console illustrates graphically the positionof transceivers in the area when available, as well as obstacles andother cranes. When transceivers are used as RFID tags on inventoriedcomponents for crane picks, the display console may display a graphicalview of the parts to pick and the location to move them to.

Those of ordinary skill in the art will realize that the description ofthe method and transceiver for preventing accidental collisions areillustrative only and are not intended to be in any way limiting. Otherembodiments will readily suggest themselves to such persons withordinary skill in the art having the benefit of the present disclosure.Furthermore, the disclosed method and transceiver may be customized tooffer valuable solutions to existing needs and problems related toworksite hazards.

In the interest of clarity, not all of the routine features of theimplementations of the method and transceiver are shown and described.It will, of course, be appreciated that in the development of any suchactual implementation of the method and transceiver, numerousimplementation specific decisions may need to be made in order toachieve the developer's specific goals, such as compliance withapplication-, system-, network- and business-related constraints, andthat these specific goals will vary from one implementation to anotherand from one developer to another. Moreover, it will be appreciated thata development effort might be complex and time consuming, but wouldnevertheless be a routine undertaking of engineering for those ofordinary skill in the field of worksite safety having the benefit of thepresent disclosure.

In accordance with the present disclosure, the components, processoperations, and/or data structures described herein may be implementedusing various types of operating systems, computing platforms, networkdevices, computer programs, and/or general purpose machines. Inaddition, those of ordinary skill in the art will recognize that devicesof a less general purpose nature, such as hardwired devices, fieldprogrammable gate arrays (FPGAs), application specific integratedcircuits (ASICs), or the like, may also be used. Where a methodcomprising a series of operations is implemented by a computer or amachine and those operations may be stored as a series of instructionsreadable by the machine, they may be stored on a tangible medium.

Systems and modules described herein may comprise software, firmware,hardware, or any combination(s) of software, firmware, or hardwaresuitable for the purposes described herein. Software and other modulesmay reside on servers, workstations, personal computers, computerizedtablets, personal digital assistants (PDA), and other devices suitablefor the purposes described herein. Software and other modules may beaccessible via local memory, via a network, via a browser or otherapplication or via other means suitable for the purposes describedherein. Data structures described herein may comprise computer files,variables, programming arrays, programming structures, or any electronicinformation storage schemes or methods, or any combinations thereof,suitable for the purposes described herein.

Example Environment for Warning of Proximity in a Worksite

With reference to FIG. 26, process 2600 is a process for warning ofproximity in a worksite. In one embodiment, process 2600 is computerimplemented methods that are carried out by processors and electricalcomponents under the control of computer-usable and computer executableinstructions. The computer-usable and computer executable instructionsreside, for example, in data storage features such as computer-usablevolatile and non-volatile memory. However, the computer-usable andcomputer executable instructions may reside in any type ofnon-transitory computer-usable storage medium that can be read by acomputer. In one embodiment, process 2600 is performed by the componentsof FIGS. 1A, 1B, 9-13, 17, 18, and 22-25. In one embodiment, the methodsmay reside in a computer-usable storage medium having instructionsembodied therein that when executed cause a computer system to performthe method.

At 2602, a second transceiver is detected at a first transceiver,wherein the first transceiver is a mobile wearable device, and whereinthe first transceiver and the second transceiver are located at aworksite. For example, the first transceiver may be transceiver 2204 andthe second transceiver may be transceiver 2208 of FIG. 22. The firsttransceiver may detect another transceiver via receiving a wirelesssignal. The signal may be sent over wideband, 900 Mhz or using anotherfrequency or technique. The first and second transceivers may beassociated with or coupled to an object such as object 2206 of FIG. 22.

At 2604, an ad-hoc network is established, at the first transceiver,between the first transceiver and the second transceiver. The ad-hocnetwork may be formed between two transceivers that are in contact withone another over particular frequencies. The use of particularfrequencies ensures that the transceivers are physically proximate toone another because of the range of the particular frequencies. Thead-hoc network may include the two transceivers and may also include anynumber of additional transceivers.

At 2606, a distance is calculated, at the first transceiver, in threedimensions between the first transceiver and the second transceiverbased on the detecting the second transceiver. For example, processor2312 of FIG. 23 may be used to calculate the distance. Processor 2312may calculate the location and the distance using a three dimensionalcoordinate system.

At 2608, a first safety envelope is defined, at the first transceiver,about the first transceiver and a second safety envelope about thesecond transceiver. The first safety envelope may be stored in memorysuch as memory 2310 of FIG. 23.

At 2610, an alarm is issued, at the first transceiver, when the firstsafety envelope comes in contact with the second safety envelope. Forexample, processor 2312 of FIG. 23 may calculate that either the firstor second transceiver, or both, have moved and their respective safetyenvelopes are in contact. The alarm may be an audible sound, a visiblelight, a flashing light, or a visual display. The alarm may change inintensity dependent upon the length of time the safety envelopes are incontact with one another or the amount of contact increases. The alarmmay continue until the safety envelopes are no longer in contact withone another.

With reference to FIG. 27, process 2700 is a process for warning ofproximity in a worksite. In one embodiment, process 2700 is computerimplemented methods that are carried out by processors and electricalcomponents under the control of computer-usable and computer executableinstructions. The computer-usable and computer executable instructionsreside, for example, in data storage features such as computer-usablevolatile and non-volatile memory. However, the computer-usable andcomputer executable instructions may reside in any type ofnon-transitory computer-usable storage medium that can be read by acomputer. In one embodiment, process 2700 is performed by the componentsof FIGS. 1A, 1B, 9-13, 17, 18, and 22-25. In one embodiment, the methodsmay reside in a computer-usable storage medium having instructionsembodied therein that when executed cause a computer system to performthe method.

At 2702, a first transceiver and a second transceiver are detected at abase station, wherein the first transceiver is a mobile wearable device,and wherein the first transceiver, the second transceiver, and the basestation are located at a worksite. For example, the base station may be2202, the first transceiver may be transceiver 2204 and the secondtransceiver may be transceiver 2208 of FIG. 22. The base station may bea stationary hardware device that is located in the worksite and hascomponents of a computer system such as a memory and processor. In oneembodiment, portions of the base station may be located remote to theworksite and may employ techniques such as cloud computing to carry outprocess 2700. The base station may detect a transceiver via receiving awireless signal. The signal may be sent over wideband, 900 Mhz or usinganother frequency or technique. The first and second transceivers may beassociated with or coupled to an object such as object 2206 of FIG. 22.

The base stations and transceivers may communicate with one another overparticular frequencies. The use of particular frequencies ensures thatthe transceivers are physically proximate to one another because of therange of the particular frequencies. The ad-hoc network may include thetwo transceivers and may also include any number of additionaltransceivers.

At 2704, a distance is calculated, at the base station, in threedimensions between the first transceiver and the second transceiverbased on the detecting the first transceiver and second transceiver. Thebase station may employ computer memory and processors to perform thecalculations in a three dimensional co-ordinate system.

At 2706, a first safety envelope is defined, at the base station, aboutthe first transceiver and a second safety envelope about the secondtransceiver. The safety envelope may be stored in a memory of the basestation or may be calculated for each transceiver or the data for thesafety envelope may be sent by the transceiver to the base station.

At 2708, a command is sent, from the base station, to issue an alarm atthe first transceiver when the first safety envelope comes in contactwith the second safety envelope. The command may cause and alarm toissue at the transceiver. For example, the base station may calculatethat either the first or second transceiver, or both, have moved andtheir respective safety envelopes are in contact. The alarm may be anaudible sound, a visible light, a flashing light, or a visual display.The alarm may change in intensity dependent upon the length of time thesafety envelopes are in contact with one another or the amount ofcontact increases. The alarm may continue until the safety envelopes areno longer in contact with one another.

Embodiments of the present technology are thus described. While thepresent technology has been described in particular embodiments, itshould be appreciated that the present technology should not beconstrued as limited to these embodiments alone, but rather construedaccording to the following claims.

We claim:
 1. A method for warning of proximity in a worksite, saidmethod comprising: detecting a second transceiver at a firsttransceiver, wherein said first transceiver is a mobile wearable device,and wherein said first transceiver and said second transceiver arelocated at a worksite; establishing, at said first transceiver, anad-hoc network between said first transceiver and said secondtransceiver; calculating, at said first transceiver, a distance in threedimensions between said first transceiver and said second transceiverbased on said detecting said second transceiver; defining, at said firsttransceiver, a first safety envelope about said first transceiver and asecond safety envelope about said second transceiver; and issuing analarm, at said first transceiver, when said first safety envelope comesin contact with said second safety envelope.
 2. The method as recited inclaim 1 wherein said ad-hoc network comprises a plurality oftransceivers in addition to said first transceiver and said secondtransceiver.
 3. The method as recited in claim 1 wherein said firsttransceiver is associated with an object that is wearable by a personlocated in said worksite wherein said object is selected from the groupof objects consisting of: a helmet, a vest, a belt, a headset, and anarticle of clothing.
 4. The method as recited in claim 1 wherein saidsecond transceiver is a worksite object selected from the group ofworksite objects consisting of: a person, a piece of equipment, a crane,a vehicle, a tree, a building, and a partially constructed structure. 5.The method as recited in claim 1 wherein said alarm is selected from thegroup of alarms consisting of: an audible sound, a visible light, aflashing light, and a visual display.
 6. The method as recited in claim1 wherein said issuing said alarm simultaneously occurs at said firsttransceiver and said second transceiver.
 7. The method as recited inclaim 1 wherein an intensity of said alarm increases until said firstsafety envelope is no longer in contact with said second safetyenvelope.
 8. The method as recited in claim 1 wherein said firsttransceiver and said second transceiver employ wideband to communicate.9. The method as recited in claim 1 wherein said first transceiver andsaid second transceiver employ 900 megahertz (MHz) to communicate.
 10. Acomputer-usable storage medium having instructions embodied therein thatwhen executed cause a computer system to perform a method for warning ofproximity in a worksite, said method comprising: detecting a secondtransceiver at a first transceiver, wherein said first transceiver is amobile wearable device, and wherein said first transceiver and saidsecond transceiver are located at a worksite; establishing, at saidfirst transceiver, an ad-hoc network between said first transceiver andsaid second transceiver; calculating, at said first transceiver, adistance in three dimensions between said first transceiver and saidsecond transceiver based on said detecting said second transceiver;defining, at said first transceiver, a first safety envelope about saidfirst transceiver and a second safety envelope about said secondtransceiver; and issuing an alarm, at said first transceiver, when saidfirst safety envelope comes in contact with said second safety envelope.11. The computer-usable storage medium as recited in claim 10 whereinsaid ad-hoc network comprises a plurality of transceivers in addition tosaid first transceiver and said second transceiver.
 12. Thecomputer-usable storage medium as recited in claim 10 wherein said firsttransceiver is associated with an object that is wearable by a personlocated in said worksite wherein said object is selected from the groupof objects consisting of: a helmet, a vest, a belt, a headset, and anarticle of clothing.
 13. The computer-usable storage medium as recitedin claim 10 wherein said second transceiver is a worksite objectselected from the group of worksite objects consisting of: a person, apiece of equipment, a crane, a vehicle, a tree, a building, and apartially constructed structure.
 14. The computer-usable storage mediumas recited in claim 10 wherein said alarm is selected from the group ofalarms consisting of: an audible sound, a visible light, a flashinglight, and a visual display.
 15. The computer-usable storage medium asrecited in claim 10 wherein said issuing said alarm simultaneouslyoccurs at said first transceiver and said second transceiver.
 16. Thecomputer-usable storage medium as recited in claim 10 wherein anintensity of said alarm increases until said first safety envelope is nolonger in contact with said second safety envelope.
 17. Thecomputer-usable storage medium as recited in claim 10 wherein said firsttransceiver and said second transceiver employ wideband to communicate.18. The computer-usable storage medium as recited in claim 10 whereinsaid first transceiver and said second transceiver employ 900 megahertz(MHz) to communicate.
 19. A transceiver for warning of proximity in aworksite, said transceiver comprising: a memory for storing apredetermined distance defining a first safety envelope about saidtransceiver, wherein said transceiver is a mobile wearable devicelocated in said worksite; a receiver for receiving a signal from asecond transceiver and establishing an ad hoc network with between saidtransceiver and said second transceiver; a processor for calculating adistance in three dimensions between said transceiver and said secondtransceiver based on said signal from said second transceiver; and analarm component for issuing an alarm when said first safety envelopecomes in contact with a second safety envelope defined about said secondtransceiver.
 20. A method for warning of proximity in a worksite, saidmethod comprising: detecting a first transceiver and a secondtransceiver at a base station, wherein said first transceiver is amobile wearable device, and wherein said first transceiver, said secondtransceiver, and said base station are located at a worksite;calculating, at said base station, a distance in three dimensionsbetween said first transceiver and said second transceiver based on saiddetecting said first transceiver and second transceiver; defining, atsaid base station, a first safety envelope about said first transceiverand a second safety envelope about said second transceiver; and sendinga command, from said base station, to issue an alarm at said firsttransceiver when said first safety envelope comes in contact with saidsecond safety envelope.
 21. The method as recited in claim 20 whereinsaid base station detects a plurality of transceivers each with a safetyenvelope in addition to said first transceiver and said secondtransceiver.
 22. The method as recited in claim 20 wherein said firsttransceiver is associated with an object that is wearable by a personlocated in said worksite wherein said object is selected from the groupof objects consisting of: a helmet, a vest, a belt, a headset, and anarticle of clothing.
 23. The method as recited in claim 20 wherein saidsecond transceiver is a worksite object selected from the group ofworksite objects consisting of: a person, a piece of equipment, a crane,a vehicle, a tree, a building, and a partially constructed structure.24. The method as recited in claim 20 wherein said alarm is selectedfrom the group of alarms consisting of: an audible sound, a visiblelight, a flashing light, and a visual display.
 25. The method as recitedin claim 20 wherein said sending said command sends commands to issuealarms to simultaneously occur at said first transceiver and said secondtransceiver.
 26. The method as recited in claim 20 wherein an intensityof said alarm increases until said first safety envelope is no longer incontact with said second safety envelope.
 27. The method as recited inclaim 20 wherein said first transceiver and said second transceiveremploy wideband to communicate.
 28. The method as recited in claim 20wherein said first transceiver and said second transceiver employ 900megahertz (MHz) to communicate.
 29. A computer-usable storage mediumhaving instructions embodied therein that when executed cause a computersystem to perform a method for warning of proximity in a worksite, saidmethod comprising: detecting a first transceiver and a secondtransceiver at a base station, wherein said first transceiver is amobile wearable device, and wherein said first transceiver, said secondtransceiver, and said base station are located at a worksite;calculating, at said base station, a distance in three dimensionsbetween said first transceiver and said second transceiver based on saiddetecting said first transceiver and second transceiver; defining, atsaid base station, a first safety envelope about said first transceiverand a second safety envelope about said second transceiver; and sendinga command, from said base station, to issue an alarm at said firsttransceiver when said first safety envelope comes in contact with saidsecond safety envelope.
 30. The computer-usable storage medium asrecited in claim 29 wherein said base station detects a plurality oftransceivers each with a safety envelope in addition to said firsttransceiver and said second transceiver.
 31. The computer-usable storagemedium as recited in claim 29 wherein said first transceiver isassociated with an object that is wearable by a person located in saidworksite wherein said object is selected from the group of objectsconsisting of: a helmet, a vest, a belt, a headset, and an article ofclothing.
 32. The computer-usable storage medium as recited in claim 29wherein said second transceiver is a worksite object selected from thegroup of worksite objects consisting of: a person, a piece of equipment,a crane, a vehicle, a tree, a building, and a partially constructedstructure.
 33. The computer-usable storage medium as recited in claim 29wherein said alarm is selected from the group of alarms consisting of:an audible sound, a visible light, a flashing light, and a visualdisplay.
 34. The computer-usable storage medium as recited in claim 29wherein said sending said command sends commands to issue alarms tosimultaneously occur at said first transceiver and said secondtransceiver.
 35. The computer-usable storage medium as recited in claim29 wherein an intensity of said alarm increases until said first safetyenvelope is no longer in contact with said second safety envelope. 36.The computer-usable storage medium as recited in claim 29 wherein saidfirst transceiver and said second transceiver employ wideband tocommunicate.
 37. The computer-usable storage medium as recited in claim29 wherein said first transceiver and said second transceiver employ 900megahertz (MHz) to communicate.